Medical dictionary

A medical dictionary is a dictionary of terms used in the field of medicine. Also see pocket medical dictionary

Dictionary of medicine[edit | edit source]

Homo sapiens - the only surviving hominid; species to which modern man belongs; bipedal primate having language and ability to make and use complex tools; brain volume at least 1400 cc
Laceration - the act of lacerating; a torn ragged wound
Microcephaly - an abnormally small head and underdeveloped brain
Movement - the act of changing the location of something; the driving and regulating parts of a mechanism (as of a watch or clock); a major self-contained part of a symphony or sonata; a natural event that involves a change in the position or location of something; a group of people with a common ideology who try together to achieve certain general goals; the act of changing location from one place to another; a change of position that does not entail a change of location; a series of actions advancing a principle or tending toward a particular end; a general tendency to change (as of opinion); an optical illusion of motion produced by viewing a rapid succession of still pictures of a moving object; a euphemism for defecation
Myeloid leukemia - chronic leukemia characterized by granular leukocytes; more common in older people
abdomen - the region of the body of a vertebrate between the thorax and the pelvis; the cavity containing the major viscera; in mammals it is separated from the thorax by the diaphragm
abdominal cavity - the cavity containing the major viscera; in mammals it is separated from the thorax by the diaphragm
abdominal muscle - the muscles of the abdomen
abdominal pregnancy - ectopic pregnancy in the abdominal cavity
abducens nerve - a small motor nerve supplying the lateral rectus muscle of the eye
abetalipoproteinemia - a rare inherited disorder of fat metabolism; characterized by severe deficiency of beta-lipoproteins and abnormal red blood cells (acanthocytes) and abnormally low cholesterol levels
ablation - surgical removal of a body part or tissue; the erosive process that reduces the size of glaciers
abnormal - much greater than the normal; not normal; not typical or usual or regular or conforming to a norm; departing from the normal in e.g. intelligence and development
abomasum - the fourth compartment of the stomach of a ruminant; the one where digestion takes place
abrasion - erosion by friction; an abraded area where the skin is torn or worn off; the wearing down of rock particles by friction due to water or wind or ice
abruptio placentae - a disorder of pregnancy in which the placenta prematurely separates from the wall of the uterus
abscess - symptom consisting of a localized collection of pus surrounded by inflamed tissue
abulia - a loss of will power
acanthocephala - phylum or class of elongated wormlike parasites that live in the intestines of vertebrates: spiny-headed worms
acanthocyte - an abnormal red blood cell that has thorny projections of protoplasm
acantholysis - a breakdown of a cell layer in the epidermis (as in pemphigus)
acanthoma - a neoplasm originating in the epidermis
acanthosis nigricans - a skin disease characterized by dark wartlike patches in the body folds; can be benign or malignant
accessory nerve - arises from two sets of roots (cranial and spinal) that unite to form the nerve
acclimatization - adaptation to a new climate (a new temperature or altitude or environment)
accreditation - the act of granting credit or recognition (especially with respect to educational institution that maintains suitable standards)
ace inhibitor - antihypertensive drug that blocks the formation of angiotensin in the kidney, leading to relaxation of the arteries; promotes the excretion of salt and water by inhibiting the activity of the angiotensin converting enzyme; also used to treat congestive heart failure
acebutolol - an oral beta blocker (trade name Sectral) used in treating hypertension
acetaldehyde - a colorless volatile water-soluble liquid aldehyde used chiefly in manufacture of acetic acid and perfumes and drugs
acetaminophen - an analgesic for mild pain; also used as an antipyretic; (Datril, Tylenol, Panadol, Phenaphen, Tempra, and Anacin III are trademarks of brands of acetaminophen tablets)
acetate - a salt or ester of acetic acid; a fabric made from fibers of cellulose acetate
acetic acid - a colorless pungent liquid widely used in manufacturing plastics and pharmaceuticals
acetone - the simplest ketone; a highly inflammable liquid widely used as an organic solvent and as material for making plastics
acetylation - the process of introducing an acetyl group into a compound
acetylcholine - a neurotransmitter that is a derivative of choline; released at the ends of nerve fibers in the somatic and parasympathetic nervous systems
achilles tendon - a large tendon that runs from the heel to the calf
achlorhydria - an abnormal deficiency or absence of free hydrochloric acid in the gastric juice; often associated with severe anemias and cancer of the stomach
achondroplasia - an inherited skeletal disorder beginning before birth; cartilage is converted to bone resulting in dwarfism
acid - having the characteristics of an acid; harsh or corrosive in tone; being sour to the taste; street name for lysergic acid diethylamide; any of various water-soluble compounds having a sour taste and capable of turning litmus red and reacting with a base to form a salt
acidosis - abnormally high acidity (excess hydrogen-ion concentration) of the blood and other body tissues
acne vulgaris - the most common form of acne; usually affects people from puberty to young adulthood
acne - an inflammatory disease involving the sebaceous glands of the skin; characterized by papules or pustules or comedones
acoustic nerve - a composite sensory nerve supplying the hair cells of the vestibular organ and the hair cells of the cochlea
acrolein - a pungent colorless unsaturated liquid aldehyde made from propene
acromegaly - enlargement of bones of hands and feet and face; often accompanied by headache and muscle pain and emotional disturbances; caused by overproduction of growth hormone by the anterior pituitary gland (due to a tumor)
acromion - the outermost point of the spine of the shoulder blade
acrosome - a process at the anterior end of a sperm cell that produces enzymes to facilitate penetration of the egg
acrylamide - a white crystalline amide of propenoic acid can damage the nervous system and is carcinogenic in laboratory animals
acrylonitrile - a colorless liquid unsaturated nitrile made from propene
actin - one of the proteins into which actomyosin can be split; can exist in either a globular or a fibrous form
actinic keratosis - an overgrowth of skin layers resulting from extended exposure to the sun
actinomyces - soil-inhabiting saprophytes and disease-producing plant and animal parasites
actinomycetaceae - filamentous anaerobic bacteria
actinomycetales - filamentous or rod-shaped bacteria
actinomycin - any of various red antibiotics isolated from soil bacteria
actinomycosis - disease of cattle that can be transmitted to humans; results from infection with actinomycetes; characterized by hard swellings that exude pus through long sinuses
action potential - the local voltage change across the cell wall as a nerve impulse is transmitted
acupressure - treatment of symptoms by applying pressure with the fingers to specific pressure points on the body
acute kidney failure - renal failure associated with burns or other trauma or with acute infection or obstruction of the urinary tract
acute leukemia - rapidly progressing leukemia
acute lymphocytic leukemia - acute leukemia characterized by proliferation of immature lymphoblast-like cells in bone marrow, lymph nodes, spleen, and blood; most common in children
acute - having or experiencing a rapid onset and short but severe course; of critical importance and consequence; extremely sharp or intense; having or demonstrating ability to recognize or draw fine distinctions; of an angle; less than 90 degrees; ending in a sharp point; a mark (') placed above a vowel to indicate pronunciation
acyclovir - an oral antiviral drug (trade name Zovirax) used to treat genital herpes; does not cure the disease but relieves the symptoms
addison's disease - a glandular disorder caused by failure of function of the cortex of the adrenal gland and marked by anemia and prostration with brownish skin
adenine - (biochemistry) purine base found in DNA and RNA; pairs with thymine in DNA and with uracil in RNA
adenocarcinoma - malignant tumor originating in glandular epithelium
adenoidectomy - surgical removal of the adenoids; commonly performed along with tonsillectomy
adenoma - a benign epithelial tumor of glandular origin
adenomatous polyp - a polyp that consists of benign neoplastic tissue derived from glandular epithelium
adenosine deaminase - an enzyme found in mammals that can catalyze the deamination of adenosine into inosine and ammonia
adenosine diphosphate - an ester of adenosine that is converted to ATP for energy storage
adenosine monophosphate - a nucleotide found in muscle cells and important in metabolism; reversibly convertible to ADP and ATP
adenosine triphosphate - a nucleotide derived from adenosine that occurs in muscle tissue; the major source of energy for cellular reactions
adenosine - (biochemistry) a nucleoside that is a structural component of nucleic acids; it is present in all living cells in a combined form as a constituent of DNA and RNA and ADP and ATP and AMP
adenosis - a disorder of the glands of the body
adenovirus - any of a group of viruses including those that in humans cause upper respiratory infections or infectious pinkeye
adipose tissue - a kind of body tissue containing stored fat that serves as a source of energy; it also cushions and insulates vital organs
adoption - the act of accepting with approval; favorable reception; a legal proceeding that creates a parent-child relation between persons not related by blood; the adopted child is entitled to all privileges belonging to a natural child of the adoptive parents (including the right to inherit); the appropriation (of ideas or words etc) from another source
adrenal cortex - the cortex of the adrenal gland; secretes corticosterone and sex hormones
adrenal gland - either of a pair of complex endocrine glands situated near the kidney
adrenal medulla - the medulla of the adrenal gland; secretes epinephrine
adrenalectomy - surgical removal of one or both adrenal glands
adsorption - the accumulation of molecules of a gas to form a thin film on the surface of a solid
adventitia - an enveloping or covering membrane or layer of body tissue
aerobic exercise - exercise that increases the need for oxygen
aerobic - depending on free oxygen or air; based on or using the principles of aerobics; enhancing respiratory and circulatory efficiency
aerobiosis - life sustained in the presence of air or oxygen
aerosol - a dispenser that holds a substance under pressure and that can release it as a fine spray (usually by means of a propellant gas); a cloud of solid or liquid particles in a gas
afferent neuron - a neuron conducting impulses inwards to the brain or spinal cord
afibrinogenemia - the absence of fibrinogen in the plasma leading to prolonged bleeding
aflatoxin - a potent carcinogen from the fungus Aspergillus; can be produced and stored for use as a bioweapon
agammaglobulinemia - a rare immunological disorder characterized by the virtual absence of gamma globulin in the blood and consequent susceptibility to infection
agaricales - typical gilled mushrooms belonging to the subdivision Basidiomycota
age - how long something has existed; a time in life (usually defined in years) at which some particular qualification or power arises; a late time of life; a prolonged period of time; an era of history having some distinctive feature; verb begin to seem older; get older; make older; grow old or older
agent orange - a herbicide used in the Vietnam War to defoliate forest areas
agglutination test - a blood test used to identify unknown antigens; blood with the unknown antigen is mixed with a known antibody and whether or not agglutination occurs helps to identify the antigen; used in tissue matching and blood grouping and diagnosis of infections
agglutinin - an antibody that causes agglutination of a specific antigen
aggression - violent action that is hostile and usually unprovoked; deliberately unfriendly behavior; the act of initiating hostilities; a disposition to behave aggressively; a feeling of hostility that arouses thoughts of attack
aging - growing old; the organic process of growing older and showing the effects of increasing age; acquiring desirable qualities by being left undisturbed for some time
agitation - the act of agitating something; causing it to move around (usually vigorously); disturbance usually in protest; the feeling of being agitated; not calm; a state of agitation or turbulent change or development; a mental state of extreme emotional disturbance
agnosia - inability to recognize objects by use of the senses
agonist - (biochemistry) a drug that can combine with a receptor on a cell to produce a physiological reaction; a muscle that contracts while another relaxes; someone involved in a contest or battle (as in an agon); the principal character in a work of fiction
agoraphobia - a morbid fear of open spaces (as fear of being caught alone in some public place)
agranulocytosis - an acute blood disorder (often caused by radiation or drug therapy) characterized by severe reduction in granulocytes
agraphia - a loss of the ability to write or to express thoughts in writing because of a brain lesion
agriculture - the class of people engaged in growing food; the practice of cultivating the land or raising stock; a large-scale farming enterprise; the federal department that administers programs that provide services to farmers (including research and soil conservation and efforts to stabilize the farming economy); created in 1862
agrobacterium tumefaciens - the bacteria that produce crown gall disease in plants
agrobacterium - small motile bacterial rods that can reduce nitrates and cause galls on plant stems
aids - a serious (often fatal) disease of the immune system transmitted through blood products especially by sexual contact or contaminated needles
air embolism - obstruction of the circulatory system caused by an air bubble as, e.g., accidentally during surgery or hypodermic injection or as a complication from scuba diving; pain resulting from rapid change in pressure
akinesia - motionlessness attributable to a temporary paralysis
alanine - a crystalline amino acid that occurs in many proteins
albinism - the congenital absence of pigmentation in the eyes and skin and hair
albumin - a simple water-soluble protein found in many animal tissues and liquids
albuminuria - the presence of excessive protein (chiefly albumin but also globulin) in the urine; usually a symptom of kidney disorder
albuterol - a bronchodilator (trade names Ventolin or Proventil) used for asthma and emphysema and other lung conditions; available in oral or inhalant forms; side effects are tachycardia and shakiness
alcohol abuse - excessive use of alcohol and alcoholic drinks
alcoholism - habitual intoxication; prolonged and excessive intake of alcoholic drinks leading to a breakdown in health and an addiction to alcohol such that abrupt deprivation leads to severe withdrawal symptoms; an intense persistent desire to drink alcoholic beverages to excess
aldehyde - any of a class of highly reactive chemical compounds; used in making resins and dyes and organic acids
aldosterone - a corticosteroid hormone that is secreted by the cortex of the adrenal gland; regulates salt (sodium and potassium) and water balance
alendronate - a tablet (trade name Fosamax) prescribed to prevent or treat osteoporosis in women after menopause
alexia - inability to perceive written words
aliquot - signifying an exact divisor or factor of a quantity; an integer that is an exact divisor of some quantity
alkaloid - natural bases containing nitrogen found in plants
alkalosis - abnormally high alkalinity (low hydrogen-ion concentration) of the blood and other body tissues
alkane - a series of non-aromatic saturated hydrocarbons with the general formula CnH(2n+2)
alkaptonuria - a rare recessive metabolic anomaly marked by ochronosis and the presence of alkapton in the urine
allele - either of a pair (or series) of alternative forms of a gene that can occupy the same locus on a particular chromosome and that control the same character
allergen - any substance that can cause an allergy
allergic reaction - hypersensitivity reaction to a particular allergen; symptoms can vary greatly in intensity
allergic - having an allergy or peculiar or excessive susceptibility (especially to a specific factor); characterized by or caused by allergy
allopurinol - a drug (trade name Zyloprim) used to treat gout and other conditions in which there is an excessive buildup of uric acid
alloy - a mixture containing two or more metallic elements or metallic and nonmetallic elements usually fused together or dissolving into each other when molten; the state of impairing the quality or reducing the value of something; verb make an alloy of; lower in value by increasing the base-metal content
alopecia areata - patchy baldness
alopecia - loss of hair (especially on the head) or loss of wool or feathers; in humans it can result from heredity or hormonal imbalance or certain diseases or drugs and treatments (chemotherapy for cancer)
alpha fetoprotein - an abnormally large amount of this fetoprotein in the fetus can signal an abnormality of the neural tube (as spina bifida or anencephaly)
alpha globulin - a globulin in blood plasma or serum that is alkaline and has great electrophoretic mobility
alphavirus - an arbovirus of the family Togaviridae that can cause a variety of encephalitis in horses
alprazolam - an antianxiety agent (trade name Xanax) of the benzodiazepine class
altitude - elevation especially above sea level or above the earth's surface; the perpendicular distance from the base of a geometric figure to opposite vertex (or side if parallel); angular distance above the horizon (especially of a celestial object)
aluminum hydroxide - white crystalline compound that occurs naturally as the mineral gibbsite
aluminum oxide - any of various forms of aluminum oxide occurring naturally as corundum
aluminum - a silvery ductile metallic element found primarily in bauxite
alveolar rhabdomyosarcoma - form of rhabdomyosarcoma occuring mainly in adolescents and young adults
alveolar ridge - a ridge that forms the borders of the upper and lower jaws and contains the sockets of the teeth
amblyopia - visual impairment without apparent organic pathology
ambulance - a vehicle that takes people to and from hospitals
amebiasis - infection by a disease-causing ameba
amelia - congenital absence of an arm or leg
ameloblast - a cell from which tooth enamel develops
amelogenesis - the developmental process of forming tooth enamel
amenorrhea - absence or suppression of normal menstrual flow
americium - a radioactive transuranic metallic element; discovered by bombarding uranium with helium atoms
amide - any organic compound containing the group -CONH2
amine - a compound derived from ammonia by replacing hydrogen atoms by univalent hydrocarbon radicals
amino acid - organic compounds containing an amino group and a carboxylic acid group
aminophylline - a theophylline derivative that is used as a bronchodilator in the treatment of bronchial asthma, emphysema, and bronchitis
amiodarone - an antiarrhythmic drug (trade name Cordarone) that has potentially fatal side effects and is used to control serious heart rhythm problems only when safer agents have been ineffective
amitriptyline - a tricyclic antidepressant drug (trade name Elavil) with serious side effects; interacts with many other medications
ammonia - a pungent gas compounded of nitrogen and hydrogen (NH3); a water solution of ammonia
ammonium chloride - a white salt used in dry cells
amnesia - partial or total loss of memory
amniocentesis - (pregnancy) extraction by centesis of amniotic fluid from a pregnant woman (after the 15th week of pregnancy) to aid in the diagnosis of fetal abnormalities
amnion - thin innermost membranous sac enclosing the developing embryo of higher vertebrates (reptiles, birds and mammals)
amniotic fluid - the serous fluid in which the embryo is suspended inside the amnion
amoeba - naked freshwater or marine or parasitic protozoa that form temporary pseudopods for feeding and locomotion
amoxicillin - an antibiotic; a semisynthetic oral penicillin (trade names Amoxil and Larotid and Polymox and Trimox and Augmentin) used to treat bacterial infections
ampere - the basic unit of electric current adopted under the Systeme International d'Unites; a former unit of electric current (slightly smaller than the SI ampere)
amphetamine - a central nervous system stimulant that increases energy and decreases appetite; used to treat narcolepsy and some forms of depression
ampicillin - semisynthetic penicillin (trade names Principen and Polycillin and SK-Ampicillin)
ampule - a small bottle that contains a drug (especially a sealed sterile container for injection by needle)
amputation - a surgical removal of all or part of a limb; a condition of disability resulting from the loss of one or more limbs
amygdala - an almond-shaped neural structure in the anterior part of the temporal lobe of the cerebrum; intimately connected with the hypothalamus and the hippocampus and the cingulate gyrus; as part of the limbic system it plays an important role in motivation and emotional behavior
amygdalin - a bitter cyanogenic glucoside extracted from the seeds of apricots and plums and bitter almonds
amylase - any of a group of proteins found in saliva and pancreatic juice and parts of plants; help convert starch to sugar
amyloid - resembling starch; (pathology) a waxy translucent complex protein resembling starch that results from degeneration of tissue; a non-nitrogenous food substance consisting chiefly of starch; any substance resembling starch
amyloidosis - a disorder characterized by deposit of amyloid in organs or tissues; often secondary to chronic rheumatoid arthritis or tuberculosis or multiple myeloma
amyotrophic lateral sclerosis - thickening of tissue in the motor tracts of the lateral columns and anterior horns of the spinal cord; results in progressive muscle atrophy that starts in the limbs
anabolism - the synthesis in living organisms of more complex substances (e.g., living tissue) from simpler ones together with the storage of energy
anaerobic - living or active in the absence of free oxygen; not aerobic
analgesia - absence of the sense of pain without loss of consciousness
analgesic - capable of relieving pain; a medicine used to relieve pain
analog - of a circuit or device having an output that is proportional to the input; something having the property of being analogous to something else
analysis - an investigation of the component parts of a whole and their relations in making up the whole; the abstract separation of a whole into its constituent parts in order to study the parts and their relations; a branch of mathematics involving calculus and the theory of limits; sequences and series and integration and differentiation; a form of literary criticism in which the structure of a piece of writing is analyzed; the use of closed-class words instead of inflections: e.g., `the father of the bride' instead of `the bride's father'; a set of techniques for exploring underlying motives and a method of treating various mental disorders; based on the theories of Sigmund Freud
analytical balance - a beam balance of great precision used in quantitative chemical analysis
anaphase - the stage of meiosis or mitosis when chromosomes move toward opposite ends of the nuclear spindle
anaphylaxis - hypersensitivity reaction to the ingestion or injection of a substance (a protein or drug) resulting from prior contact with a substance
anaplasia - loss of structural differentiation within a cell or group of cells often with increased capacity for multiplication, as in a malignant tumor
anasarca - generalized edema with accumulation of serum in subcutaneous connective tissue
anatomist - an expert in anatomy
anatomy - a detailed analysis; the branch of morphology that deals with the structure of animals; alternative names for the body of a human being
androgen - male sex hormone that is produced in the testes and responsible for typical male sexual characteristics
androsterone - an androgenic hormone that is less active than testosterone
anemia - genus of terrestrial or lithophytic ferns having pinnatifid fronds; chiefly of tropical America; a deficiency of red blood cells; a lack of vitality
anencephaly - a defect in brain development resulting in small or missing brain hemispheres
anesthesia - loss of bodily sensation with or without loss of consciousness
anesthesiologist - a specialist who administers an anesthetic to a patient before he is treated
anesthesiology - the branch of medical science that studies and applies anesthetics
anesthetic - characterized by insensibility; a drug that causes temporary loss of bodily sensations
aneuploidy - an abnormality involving a chromosome number that is not an exact multiple of the haploid number (one chromosome set is incomplete)
aneurysm - a cardiovascular disease characterized by a saclike widening of an artery resulting from weakening of the artery wall
anger - a strong emotion; a feeling that is oriented toward some real or supposed grievance; the state of being angry; belligerence aroused by a real or supposed wrong (personified as one of the deadly sins); verb make angry; become angry
angina pectoris - a heart condition marked by paroxysms of chest pain due to reduced oxygen to the heart
angiogenesis inhibitor - a drug that is designed to prevent the growth of blood vessels that nourish tumors
angiography - roentgenographic examination of blood vessels after injection of a radiopaque contrast medium; produces an angiogram
angiotensin i - a physiologically inactive form of angiotensin that is the precursor to angiotensin II
angiotensin - any of several vasoconstrictor substances (trade name Hypertensin) that cause narrowing of blood vessels
anhedonia - an inability to experience pleasure
anhidrosis - failure of the sweat glands
aniline - oily poisonous liquid amine obtained from nitrobenzene and used to make dyes and plastics and medicines
anion - a negatively charged ion
anisometropia - difference in the refractive power of the two eyes
ankle - a gliding joint between the distal ends of the tibia and fibula and the proximal end of the talus
ankyloglossia - a congenital anomaly in which the mucous membrane under the tongue is too short limiting the mobility of the tongue
ankylosing spondylitis - a chronic form of spondylitis primarily in males and marked by impaired mobility of the spine; sometimes leads to ankylosis
ankylosis - abnormal adhesion and rigidity of the bones of a joint
annelida - segmented worms: earthworms; lugworms; leeches
anomia - type genus of the family Anomiidae: saddle oysters; inability to name objects or to recognize written or spoken names of objects
anoplura - sucking lice
anorexia nervosa - (psychiatry) a psychological disorder characterized by somatic delusions that you are too fat despite being emaciated
anorexia - a prolonged disorder of eating due to loss of appetite
anorgasmia - absence of an orgasm in sexual relations
anosmia - absence of the sense of smell (as by damage to olfactory nasal tissue or the olfactory nerve or by obstruction of the nasal passages)
anovulation - the absence of ovulation due to immaturity or post-maturity or pregnancy or oral contraceptive pills or dysfunction of the ovary
anoxia - severe hypoxia; absence of oxygen in inspired gases or in arterial blood or in the tissues
anserine - having or revealing stupidity; of or resembling a goose
antacid - acting to neutralize acid (especially in the stomach); an agent that counteracts or neutralizes acidity (especially in the stomach)
anterior - earlier in time; of or near the head end or toward the front plane of the body; a tooth situated at the front of the mouth
anthelmintic - capable of expelling or destroying parasitic worms; a medication capable of causing the evacuation of parasitic intestinal worms
anthracosis - lung disease caused by inhaling coal dust
anthrax - a disease of humans that is not communicable; caused by infection with Bacillus anthracis followed by septicemia; a highly infectious animal disease (especially cattle and sheep); it can be transmitted to people
anthropometry - measurement and study of the human body and its parts and capacities
antibiotic - of or relating to antibiotic drugs; a chemical substance derivable from a mold or bacterium that kills microorganisms and cures infections
antibody - any of a large variety of proteins normally present in the body or produced in response to an antigen which it neutralizes, thus producing an immune response
anticoagulant - medicine that prevents or retards the clotting of blood
anticonvulsant - a drug used to treat or prevent convulsions (as in epilepsy)
antidepressant - any of a class of drugs used to treat depression; often have undesirable side effects
antidiarrheal - a drug used to control or stop diarrhea
antidote - a remedy that stops or controls the effects of a poison
antiemetic - a drug that prevents or alleviates nausea and vomiting
antifungal agent - any agent that destroys or prevents the growth of fungi
antigen - any substance (as a toxin or enzyme) that stimulates an immune response in the body (especially the production of antibodies)
antihistamine - a medicine used to treat allergies and hypersensitive reactions and colds; works by counteracting the effects of histamine on a receptor site
antimalarial - a medicinal drug used to prevent or treat malaria
antimetabolite - an antineoplastic drug that inhibits the utilization of a metabolite
antimony - a metallic element having four allotropic forms; used in a wide variety of alloys; found in stibnite
antineoplastic antibiotic - an antibiotic drug used as an antineoplastic in chemotherapy
antineoplastic - used in the treatment of cancer; any of several drugs that control or kill neoplastic cells; used in chemotherapy to kill cancer cells; all have unpleasant side effects that may include nausea and vomiting and hair loss and suppression of bone marrow function
antioxidant - substance that inhibits oxidation or inhibits reactions promoted by oxygen or peroxides
antipsychotic agent - tranquilizer used to treat psychotic conditions when a calming effect is desired
antipyretic - preventing or alleviating fever; any medicine that lowers body temperature to prevent or alleviate fever
antisepsis - the process of inhibiting the growth and multiplication of microorganisms; (of non-living objects) the state of being free of pathogenic organisms
antiserum - blood serum containing antibodies against specific antigens; provides immunity to a disease
antitoxin - an antibody that can neutralize a specific toxin
antivenin - an antitoxin that counteracts the effects of venom from the bite of a snake or insect or other animal
antiviral agent - any drug that destroys viruses
anuria - inability to urinate
anus - excretory opening at the end of the alimentary canal
anxiety disorder - a cover term for a variety of mental disorders in which severe anxiety is a salient symptom
anxiety - a vague unpleasant emotion that is experienced in anticipation of some (usually ill-defined) misfortune; a relatively permanent state of anxiety occurring in a variety of mental disorders
aorta - the large trunk artery that carries blood from the left ventricle of the heart to branch arteries
aortic aneurysm - an aneurysm of the aorta
aortic valve - a semilunar valve between the left ventricle and the aorta; prevents blood from flowing from the aorta back into the heart
aortitis - inflammation of the aorta
apathy - the trait of lacking enthusiasm for or interest in things generally; an absence of emotion or enthusiasm
apatite - a common complex mineral consisting of calcium fluoride phosphate or calcium chloride phosphate; a source of phosphorus
apgar score - an assessment of the physical condition of a newborn infant; involves heart rate and muscle tone and respiratory effort and color and reflex responsiveness
aphakia - absence of the natural lens of the eye (usually resulting from the removal of cataracts)
aphasia - inability to use or understand language (spoken or written) because of a brain lesion
apheresis - a procedure in which blood is drawn and separated into its components by dialysis; some are retained and the rest are returned to the donor by transfusion; (linguistics) omission at the beginning of a word as in `coon' for `raccoon' or `till' for `until'
aphonia - a disorder of the vocal organs that results in the loss of voice
apical - situated at an apex
aplastic anemia - anemia characterized by pancytopenia resulting from failure of the bone marrow; can be caused by neoplasm or by toxic exposure
aplysia - type genus of the family Aplysiidae
apnea - transient cessation of respiration
apoenzyme - a protein that combines with a coenzyme to form an active enzyme
apomorphine - a morphine derivative that is not as strong as morphine; used as an emetic and in small doses as a sedative
aponeurosis - any of the deeper and thicker fascia that attach muscles to bones; resemble flattened tendons
apoptosis - a type of cell death in which the cell uses specialized cellular machinery to kill itself; a cell suicide mechanism that enables metazoans to control cell number and eliminate cells that threaten the animal's survival
appearance - the act of appearing in public view; pretending that something is the case in order to make a good impression; formal attendance (in court or at a hearing) of a party in an action; outward or visible aspect of a person or thing; a mental representation; the event of coming into sight
appendectomy - surgical removal of the vermiform appendix
appendicitis - inflammation of the vermiform appendix
appendicular skeleton - the part of the skeleton that includes the pectoral girdle and the pelvic girdle and the upper and lower limbs
appendix - a vestigial process that extends from the lower end of the cecum and that resembles a small pouch; supplementary material that is collected and appended at the back of a book
appetite - a feeling of craving something
apraxia - inability to make purposeful movements
aqueous humor - the limpid fluid within the eyeball between the cornea and the lens
arbovirus - a large heterogeneous group of RNA viruses divisible into groups on the basis of the virions; they have been recovered from arthropods, bats, and rodents; most are borne by arthropods; they are linked by the epidemiologic concept of transmission between vertebrate hosts by arthropod vectors (mosquitoes, ticks, sandflies, midges, etc.) that feed on blood; they can cause mild fevers, hepatitis, hemorrhagic fever, and encephalitis
arcus senilis - an whitish deposit in the shape of an arc that is sometimes seen in the cornea
arenaviridae - a family of arborviruses carried by arthropods
arenavirus - animal viruses belonging to the family Arenaviridae
areola - small circular area such as that around the human nipple or an inflamed area around a pimple or insect bite; small space in a tissue or body part such as the area between veins on a leaf or an insect's wing
arginine - a bitter tasting amino acid found in proteins and necessary for nutrition; its absence from the diet leads to a reduced production of spermatozoa
argon - a colorless and odorless inert gas; one of the six inert gases; comprises approximately 1% of the earth's atmosphere
arousal - the act of arousing; awakening from sleep; a state of heightened physiological activity; mutual sexual fondling prior to sexual intercourse
arrhythmia - an abnormal rate of muscle contractions in the heart
arsenic trioxide - a white powdered poisonous trioxide of arsenic; used in manufacturing glass and as a pesticide (rat poison) and weed killer
arsenic - a very poisonous metallic element that has three allotropic forms; arsenic and arsenic compounds are used as herbicides and insecticides and various alloys; found in arsenopyrite and orpiment and realgar; a white powdered poisonous trioxide of arsenic; used in manufacturing glass and as a pesticide (rat poison) and weed killer
arsenical - relating to or containing arsenic; a pesticide or drug containing arsenic
arteriography - roentgenographic examination of arteries
arteriole - one of the small thin-walled arteries that end in capillaries
arteriolosclerosis - sclerosis of the arterioles
arteriosclerosis - sclerosis of the arterial walls
arteritis - inflammation of an artery
artery - a major thoroughfare that bears important traffic; a blood vessel that carries blood from the heart to the body
arthralgia - pain in a joint or joints
arthritis - inflammation of a joint or joints
arthrocentesis - removal of fluid from a joint by centesis
arthrodesis - the surgical fixation of a joint which is intended to result in bone fusion
arthropathy - a pathology or abnormality of a joint
arthroplasty - surgical reconstruction or replacement of a malformed or degenerated joint
arthropoda - jointed-foot invertebrates: arachnids; crustaceans; insects; millipedes; centipedes
arthroscope - a type of endoscope that is inserted into a joint for visual examination
arthroscopy - a minimally invasive operation to repair a damaged joint; the surgeon examines the joint with an arthroscope while making repairs through a small incision
artificial heart - a pump that replaces the natural heart
artificial insemination - the introduction of semen into the oviduct or uterus by some means other than sexual intercourse
artificial intelligence - the branch of computer science that deal with writing computer programs that can solve problems creatively
artificial skin - a synthetic covering with two layers used experimentally to treat burn victims
arytenoid cartilage - either of two small cartilages at the back of the larynx to which the vocal folds are attached
asbestos - a fibrous amphibole; used for making fireproof articles; inhaling fibers can cause asbestosis or lung cancer
asbestosis - lung disease caused by inhaling asbestos particles
ascariasis - infestation of the human intestine with Ascaris roundworms
ascaris lumbricoides - intestinal parasite of humans and pigs
ascaris - type genus of the family Ascaridae: roundworms with a three-lipped mouth
ascending colon - the part of the large intestine that ascends from the cecum to the transverse colon
ascites - accumulation of serous fluid in peritoneal cavity
ascorbic acid - a vitamin found in fresh fruits (especially citrus fruits) and vegetables; prevents scurvy
asparaginase - antineoplastic drug (trade name Elspar) sometimes used to treat lymphoblastic leukemia
asparagine - a crystalline amino acid found in proteins and in many plants (e.g., asparagus)
aspartic acid - a crystalline amino acid found in proteins and occurring naturally in sugar beets and sugar cane
aspergillosis - disease especially in agricultural workers caused by inhalation of Aspergillus spores causing lumps in skin and ears and respiratory organs; an opportunistic infection by a fungus of the genus Aspergillus; characterized by inflammation and lesions of the ear and other organs; severe respiratory disease of birds that takes the form of an acute rapidly fatal pneumonia in young chickens and turkeys
aspergillus fumigatus - a mold causing aspergillosis in birds and man
aspergillus - genus of common molds causing food spoilage and some pathogenic to plants and animals
asphyxia - a condition in which insufficient or no oxygen and carbon dioxide are exchanged on a ventilatory basis; caused by choking or drowning or electric shock or poison gas
aspirate - a consonant proced with aspiration; verb suck in (air); proce with aspiration; of stop sounds; remove as if by suction
aspiration pneumonia - inflammation of the lungs caused by inhaling or choking on vomitus; may occur during unconsciousness (anesthesia or drunkenness or seizure or cardiac arrest)
aspiration - a will to succeed; a manner of articulation involving an audible release of breath; the act of inhaling; the drawing in of air (or other gases) as in breathing; a cherished desire
aspirin - the acetylated derivative of salicylic acid; used as an analgesic anti-inflammatory drug (trade names Bayer and Empirin) usually taken in tablet form; used as an antipyretic; slows clotting of the blood by poisoning platelets
assay - a quantitative or qualitative test of a substance (especially an ore or a drug) to determine its components; frequently used to test for the presence or concentration of infectious agents or antibodies etc.; an appraisal of the state of affairs; a written report of the results of an analysis of the composition of some substance; a substance that is undergoing an analysis of its components; verb analyze (chemical substances); make an effort or attempt
association cortex - cortical areas that are neither motor or sensory but are thought to be involved in higher processing of information
asthenia - an abnormal loss of strength
asthma - respiratory disorder characterized by wheezing; usually of allergic origin
astigmatism - (optics) defect in an optical system in which light rays from a single point fail to converge in a single focal point; (ophthalmology) impaired eyesight resulting usually from irregular conformation of the cornea
astringent - tending to draw together or constrict soft organic tissue; sour or bitter in taste; a drug that causes contraction of body tissues and canals
astrocyte - comparatively large neuroglial cell
asymptomatic - having no symptoms of illness or disease
ataxia - inability to coordinate voluntary muscle movements; unsteady movements and staggering gait
atelectasis - collapse of an expanded lung (especially in infants); also failure of pulmonary alveoli to expand at birth
atenolol - an oral beta blocker (trade name Tenormin) used in treating hypertension and angina; has adverse side effects (depression and exacerbation of congestive heart failure etc.)
atherosclerosis - a stage of arteriosclerosis involving fatty deposits (atheromas) inside the arterial walls
athetosis - a continuous succession of slow, writhing, involuntary movements of the hands and feet and other body parts
atopic dermatitis - a severe form of dermatitis characterized by atopy
atopy - an allergic reaction that becomes apparent in a sensitized person only minutes after contact
atorvastatin - an oral drug (trade name Lipitor) that is effective in lowering triglycerides; potent in reducing LDL cholesterol because higher doses can be given
atrial fibrillation - fibrillation of the muscles of the atria of the heart
atrial septal defect - an abnormal opening between the left and right atria of the heart
atrioventricular block - recurrent sudden attacks of unconsciousness caused by impaired conduction of the impulse that regulates the heartbeat
atrioventricular bundle - a bundle of modified heart muscle that transmits the cardiac impulse from the atrioventricular node to the ventricles causing them to contract
atrioventricular node - a node of specialized heart muscle located in the septal wall of the right atrium; receives impulses from the sinoatrial node and transmits them to atrioventricular bundle
atrium - the central area in a building; open to the sky; any chamber that is connected to other chambers or passageways (especially one of the two upper chambers of the heart)
atrophy - any weakening or degeneration (especially through lack of use); a decrease in size of an organ caused by disease or disuse; verb undergo atrophy
atropine - a poisonous crystalline alkaloid extracted from the nightshade family; used as an antispasmodic and to dilate the eye pupil; also administered in large amounts as an antidote for organophosphate nerve agents or organophosphate insecticides
attention - a courteous act indicating affection; a motionless erect stance with arms at the sides and feet together; assumed by military personnel during drill or review; the faculty or power of mental concentration; the process whereby a person concentrates on some features of the environment to the (relative) exclusion of others; a general interest that leads people to want to know more; the work of providing treatment for or attending to someone or something
attitude - a theatrical pose created for effect; a complex mental state involving beliefs and feelings and values and dispositions to act in certain ways; position of aircraft or spacecraft relative to a frame of reference (the horizon or direction of motion); the arrangement of the body and its limbs
attribution - assigning to a cause or source; assigning some quality or character to a person or thing
audiology - the measurement of hearing
audiometer - an instrument used to measure the sensitivity of hearing
audiometry - measuring sensitivity of hearing; the measurement of hearing
auditory area - the cortical area that receives auditory information from the medial geniculate body
auditory ossicle - ossicles of the middle ear that transmit acoustic vibrations from the eardrum to the inner ear
aura - an indication of radiant light drawn around the head of a saint; a sensation (as of a cold breeze or bright light) that precedes the onset of certain disorders such as a migraine attack or epileptic seizure; a distinctive but intangible quality surrounding a person or thing
auricular artery - artery that supplies blood to the ear
auricular vein - one of two veins serving the ear region
auscultation - listening to sounds within the body (usually with a stethoscope)
autism - (psychiatry) an abnormal absorption with the self; marked by communication disorders and short attention span and inability to treat others as people
autoantibody - an antibody acting against tissues of the organism that produces it
autogenic training - training patients in self-induced relaxation
autoimmune disorder - any of a large group of diseases characterized by abnormal functioning of the immune system that causes your immune system to produce antibodies against your own tissues
autolysis - lysis of plant or animal tissue by an internal process
autonomic ganglion - any of the ganglia of the autonomic system whose unmyelinated fibers innervate the internal organs
autonomic nervous system - the part of the nervous system of vertebrates that controls involuntary actions of the smooth muscles and heart and glands
autopsy - an examination and dissection of a dead body to determine cause of death or the changes produced by disease; verb perform an autopsy on a dead body; do a post-mortem
autoradiography - producing a radiograph by means of the radiation emitted from the specimen being photographed
autosome - any chromosome that is not a sex chromosome; appear in pairs in body cells but as single chromosomes in spermatozoa
average - lacking special distinction, rank, or status; commonly encountered; around the middle of a scale of evaluation of physical measures; approximating the statistical norm or average or expected value; lacking exceptional quality or ability; relating to or constituting the middle value of an ordered set of values (or the average of the middle two in a set with an even number of values); relating to or constituting the most frequent value in a distribution; a statistic describing the location of a distribution; verb compute the average of; achieve or reach on average; amount to or come to an average, without loss or gain
avoidance - deliberately avoiding; keeping away from or preventing from happening
awareness - having knowledge of; state of elementary or undifferentiated consciousness
awl - a pointed tool for marking surfaces or for punching small holes
axial skeleton - the part of the skeleton that includes the skull and spinal column and sternum and ribs
axial - situated on or along or in the direction of an axis; of or relating to or resembling an axis of rotation; relating to or attached to the axis
axilla - the hollow under the arm where it is joined to the shoulder
axis - the center around which something rotates; the 2nd cervical vertebra; serves as a pivot for turning the head; a straight line through a body or figure that satisfies certain conditions; in World War II the alliance of Germany and Italy in 1936 which later included Japan and other nations; the main stem or central part about which plant organs or plant parts such as branches are arranged; a group of countries in special alliance
axon - long nerve fiber that conducts away from the cell body of the neuron
azathioprine - an immunosuppressive drug (trade name Imuran) used to prevent rejection of a transplanted organ
azide - a chemical compound containing the azido group combined with an element or radical
azotemia - accumulation in the blood of nitrogenous waste products (urea) that are usually excreted in the urine
b lymphocyte - a lymphocyte derived from bone marrow that provides humoral immunity; it recognizes free antigen molecules in solution and matures into plasma cells that secrete immunoglobulin (antibodies) that inactivate the antigens
babinski reflex - extension upward of the toes when the sole of the foot is stroked firmly on the outer side from the heel to the front; normal in infants under the age of two years but a sign of brain or spinal cord injury in older persons
bacillaceae - typically rod-shaped usually Gram-positive bacteria that produce endospores
bacillus anthracis - a species of bacillus that causes anthrax in humans and in animals (cattle and swine and sheep and rabbits and mice and guinea pigs); can be used a bioweapon
bacillus subtilis - a species of bacillus found in soil and decomposing organic matter; some strains produce antibiotics
bacillus - aerobic rod-shaped spore-producing bacterium; often occurring in chainlike formations; found primarily in soil
bacitracin - a polypeptide antibiotic of known chemical structure effective against several types of Gram-positive organisms; usually applied locally
backache - an ache localized in the back
bacteremia - transient presence of bacteria (or other microorganisms) in the blood
bacteria - (microbiology) single-celled or noncellular spherical or spiral or rod-shaped organisms lacking chlorophyll that reproduce by fission; important as pathogens and for biochemical properties; taxonomy is difficult; often considered plants
bacterial toxin - any endotoxin or exotoxin formed in or elaborated by bacterial cells
bacteriology - the branch of medical science that studies bacteria in relation to disease
bacteroidaceae - family of bacteria living usually in the alimentary canal or on mucous surfaces of warm-blooded animals; sometimes associated with acute infective processes
bacteroides - type genus of Bacteroidaceae; genus of Gram-negative rodlike anaerobic bacteria producing no endospores and no pigment and living in the gut of man and animals
bagassosis - alveolitis caused by inhaling bagasse (sugarcane dust)
balanitis - inflammation of the head of the penis
bandage - a piece of soft material that covers and protects an injured part of the body; verb dress by covering or binding; wrap around with something so as to cover or enclose
barium enema - contrast medium is injected into the rectum and x-rays are taken to search for lesions
barium sulfate - a white insoluble radiopaque powder used as a pigment
barium - a soft silvery metallic element of the alkali earth group; found in barite
basal - of primary importance; serving as or forming a base; especially of leaves; located at the base of a plant or stem; especially arising directly from the root or rootstock or a root-like stem
baseline - the lines a baseball player must follow while running the bases; an imaginary line or standard by which things are measured or compared; the back line bounding each end of a tennis or handball court; when serving the server must not step over this line
basilar membrane - a membrane in the cochlea that supports the organ of Corti
basophil - a leukocyte with basophilic granules easily stained by basic stains
basophilia - the tendency of cells to stain with basic dyes
becquerel - French physicist who discovered that rays emitted by uranium salts affect photographic plates (1852-1908)
bed rest - confinement to bed continuously (as in the case of some sick or injured persons)
behavior therapy - psychotherapy that seeks to extinguish or inhibit abnormal or maladaptive behavior by reinforcing desired behavior and extinguishing undesired behavior
behavior - manner of acting or controlling yourself; (psychology) the aggregate of the responses or reactions or movements made by an organism in any situation; the action or reaction of something (as a machine or substance) under specified circumstances; (behavioral attributes) the way a person behaves toward other people
benign - pleasant and beneficial in nature or influence; kindness of disposition or manner; not dangerous to health; not recurrent or progressive (especially of a tumor)
benzene - a colorless liquid hydrocarbon; highly inflammable; carcinogenic; the simplest of the aromatic compounds
benzocaine - a white crystalline ester used as a local anesthetic
benzoyl peroxide - a white crystalline peroxide used in bleaching (flour or oils or fats) and as a catalyst for free radical reactions
bereavement - state of sorrow over the death or departure of a loved one
beriberi - avitaminosis caused by lack of thiamine (vitamin B1)
beryllium - a light strong brittle grey toxic bivalent metallic element
beta endorphin - an endorphin produced by the pituitary gland that suppresses pain
beta globulin - a globulin in blood plasma that carries iron
beta-carotene - an isomer of carotene that is found in dark green and dark yellow fruits and vegetables
beta-lactamase - enzyme produced by certain bacteria that inactivates penicillin and results in resistance to that antibiotic
beta - preliminary or testing stage of a software or hardware product; second in order of importance; the 2nd letter of the Greek alphabet; beets
betaine - a sweet tasting alkaloid that occurs in sugar beets
bicarbonate - a salt of carbonic acid (containing the anion HCO3) in which one hydrogen atom has been replaced; an acid carbonate
bicuspid - having two cusps or points (especially a molar tooth); a tooth having two cusps or points; located between the incisors and the molars
bilateral - having two sides or parts; affecting or undertaken by two parties; having identical parts on each side of an axis
bile duct - a duct formed by the hepatic and cystic ducts; opens into the duodenum
bile - a digestive juice secreted by the liver and stored in the gallbladder; aids in the digestion of fats
biliary - relating to the bile ducts or the gallbladder; relating to or containing bile
bilirubin - an orange-yellow pigment in the bile that forms as a product of hemoglobin; excess amounts in the blood produce the yellow appearance observed in jaundice
binocular vision - vision involving the use of both eyes
binomial distribution - a theoretical distribution of the number of successes in a finite set of independent trials with a constant probability of success
bioassay - appraisal of the biological activity of a substance by testing its effect on an organism and comparing the result with some agreed standard; verb subject to a bio-assay
biochemistry - the organic chemistry of compounds and processes occuring in organisms; the effort to understand biology within the context of chemistry
biofeedback - a training program in which a person is given information about physiological processes (heart rate or blood pressure) that is not normally available with the goal of gaining conscious control of them
biological clock - an innate mechanism in living organisms that controls the periodicity of many physiological functions
biological process - a process occurring in living organisms
biological - of parents and children; related by blood; pertaining to biology or to life and living things
biology - the science that studies living organisms; characteristic life processes and phenomena of living organisms; all the plant and animal life of a particular region
bioluminescence - luminescence produced by physiological processes (as in the firefly)
biomedicine - the branch of medical science that studies the ability of organisms to withstand environmental stress (as in space travel); the branch of medical science that applies biological and physiological principles to clinical practice
biophysics - physics as applied to biological problems
biopsy - examination of tissues or liquids from the living body to determine the existence or cause of a disease
biotechnology - the branch of engineering science in which biological science is used to study the relation between workers and their environments; the branch of molecular biology that studies the use of microorganisms to perform specific industrial processes
biotin - a B vitamin that aids in body growth
bipolar disorder - a mental disorder characterized by episodes of mania and depression
birth rate - the ratio of live births in an area to the population of that area; expressed per 1000 population per year
birth - the event of being born; the time when something begins (especially life); the process of giving birth; the kinship relation of an offspring to the parents; verb cause_to_be_born
bismuth - a heavy brittle diamagnetic trivalent metallic element (resembles arsenic and antimony chemically); usually recovered as a by-product from ores of other metals
blackwater fever - severe and often fatal malaria characterized by kidney damage resulting in dark urine
blastocyst - the blastula of mammals
blastoma - a tumor composed of immature undifferentiated cells
blastomycosis - any of several infections of the skin or mucous membrane caused by Blastomyces
blepharitis - inflammation of the eyelids characterized by redness and swelling and dried crusts
blepharospasm - spasm of the eyelid muscle resulting in closure of the eye
blindness - the state of being blind or lacking sight
blood bank - a place for storing whole blood or blood plasma
blood cell - either of two types of cells (erythrocytes and leukocytes) and sometimes including platelets
blood coagulation - a process in which liquid blood is changed into a semisolid mass (a blood clot)
blood glucose - glucose in the bloodstream
blood group - human blood cells (usually just the red blood cells) that have the same antigens
blood pressure - the pressure of the circulating blood against the walls of the blood vessels; results from the systole of the left ventricle of the heart; sometimes measured for a quick evaluation of a person's health
blood transfusion - the introduction of blood or blood plasma into a vein or artery
blood vessel - a vessel in which blood circulates
blood - temperament or disposition; the fluid (red in vertebrates) that is pumped by the heart; people viewed as members of a group; the descendants of one individual; a dissolute man in fashionable society; verb smear with blood, as in a hunting initiation rite, where the face of a person is smeared with the blood of the kill
body fluid - the liquid parts of the body
body odor - malodorousness resulting from a failure to bathe
body temperature - temperature of the body; normally 98.6 F or 37 C in humans; usually measured to obtain a quick evaluation of a person's health
body weight - the weight of a person's body
bone marrow - the fatty network of connective tissue that fills the cavities of bones; very tender and very nutritious tissue from marrowbones
bone - consisting of or made up of bone; a shade of white the color of bleached bones; rigid connective tissue that makes up the skeleton of vertebrates; the porous calcified substance from which bones are made; verb remove the bones from; study intensively, as before an exam
borderline - of questionable or minimal quality; a line that indicates a boundary
boric acid - any of various acids containing boron and oxygen; a white or colorless slightly acid solid that is soluble in water and ethanol; used in the manufacture of glass and paper and adhesives and in detergents and as a flux in welding; also used as an antiseptic and food preservative
boron - a trivalent metalloid element; occurs both in a hard black crystal and in the form of a yellow or brown powder
borrelia burgdorferi - cause of Lyme disease; transmitted primarily by ticks of genus Ixodes
borrelia - cause of e.g. European and African relapsing fever
botulinum toxin - any of several neurotoxins that are produced by the anaerobic bacterium Clostridium botulinum; causes muscle paralysis
botulism - food poisoning from ingesting botulin; not infectious; affects the CNS; can be fatal if not treated promptly
brachial artery - the main artery of the upper arm; a continuation of the axillary artery; bifurcates into the radial and ulnar arteries at the elbow
brachial plexus - a network of nerves formed by cervical and thoracic spinal nerves and supplying the arm and parts of the shoulder
brachycephaly - the quality of being brachycephalic
brachydactyly - abnormal shortness of fingers and toes
bradycardia - abnormally slow heartbeat
brain death - death when respiration and other reflexes are absent; consciousness is gone; organs can be removed for transplantation before the heartbeat stops
brain disorder - any disorder or disease of the brain
brain wave - (neurophysiology) rapid fluctuations of voltage between parts of the cerebral cortex that are detectable with an electroencephalograph
brain-stem - the part of the brain continuous with the spinal cord and comprising the medulla oblongata and pons and midbrain and parts of the hypothalamus
brain - that part of the central nervous system that includes all the higher nervous centers; enclosed within the skull; continuous with the spinal cord; mental ability; the brain of certain animals used as meat; that which is responsible for one's thoughts and feelings; the seat of the faculty of reason; someone who has exceptional intellectual ability and originality; verb kill by smashing someone's skull; hit on the head
breast - the front part of the trunk from the neck to the abdomen; either of two soft fleshy milk-secreting glandular organs on the chest of a woman; meat carved from the breast of a fowl; verb reach the summit; meet at breast level; confront bodily
breech presentation - delivery of an infant whose feet or buttocks appear first
bromine - a nonmetallic largely pentavalent heavy volatile corrosive dark brown liquid element belonging to the halogens; found in sea water
bromthymol blue - a dye used as an acid-base indicator
bronchial - relating to or associated with the bronchi
bronchiole - any of the smallest bronchial ducts; ending in alveoli
bronchiolitis - inflammation of the membranes lining the bronchioles
bronchitis - inflammation of the membranes lining the bronchial tubes
bronchodilator - a drug that relaxes and dilates the bronchial passageways and improves the passages of air into the lungs
bronchopneumonia - pneumonia characterized by acute inflammation of the walls of the bronchioles
bronchoscope - a slender tubular instrument used to examine the bronchial tubes
bronchospasm - a spasm of the bronchi that makes exhalation difficult and noisy; associated with asthma and bronchitis
bronchus - either of the two main branches of the trachea
brucella - an aerobic Gram-negative coccobacillus that causes brucellosis; can be used as a bioweapon
brucellosis - infectious bacterial disease of human beings transmitted by contact with infected animals or infected meat or milk products; characterized by fever and headache; an infectious disease of domestic animals often resulting in spontaneous abortion; transmittable to human beings
bruxism - involuntarily or unconsciously clenching or grinding the teeth, typically during sleep
buffer - a cushion-like device that reduces shock due to contact; a power tool used to buff surfaces; (computer science) a part of RAM used for temporary storage of data that is waiting to be sent to a device; used to compensate for differences in the rate of flow of data between components of a computer system; an ionic compound that resists changes in its pH; an implement consisting of soft material mounted on a block; used for polishing (as in manicuring); an inclined metal frame at the front of a locomotive to clear the track; verb add a buffer (a solution); protect from impact
bulbar conjunctiva - the part of the conjunctiva covering the anterior face of the sclera and the surface epithelium of the cornea
bulimia - pathologically insatiable hunger (especially when caused by brain lesions); a disorder of eating seen among young women who go on eating binges and then feel guilt and depression and self-condemnation
bulla - the round leaden seal affixed to a papal bull; (pathology) an elevation of the skin filled with serous fluid
bully - very good; a cruel and brutal fellow; verb discourage or frighten with threats or a domineering manner; intimidate; be bossy towards
bunion - a painful swelling of the bursa of the first joint of the big toe
bunyaviridae - a large family of arboviruses that affect a wide range of hosts (mainly vertebrates and arthropods)
burn - damage inflicted by fire; a place or area that has been burned (especially on a person's body); an injury caused by exposure to heat or chemicals or radiation; pain that feels hot as if it were on fire; a browning of the skin resulting from exposure to the rays of the sun; verb burn with heat, fire, or radiation; undergo combustion; cause to undergo combustion; destroy by fire; feel strong emotion, especially anger or passion; feel hot or painful; spend (significant amounts of money); burn at the stake; cause to burn or combust; shine intensely, as if with heat; get a sunburn by overexposure to the sun; burn, sear, or freeze (tissue) using a hot iron or electric current or a caustic agent; use up (energy); create by duplicating data; cause a sharp or stinging pain or discomfort
bursitis - inflammation of a bursa; frequently in the shoulder
buspirone - a drug (trade name BuSpar) designed specifically for anxiety
butanol - a flammable alcohol derived from butanes and used for solvents
butyric acid - an unpleasant smelling fatty acid found especially in butter
bypass - a road that takes traffic around the edge of a town; a surgically created shunt (usually around a damaged part); a conductor having low resistance in parallel with another device to divert a fraction of the current; verb avoid something unpleasant or laborious
cachexia - any general reduction in vitality and strength of body and mind resulting from a debilitating chronic disease
cadaver - the dead body of a human being
cadmium - a soft bluish-white ductile malleable toxic bivalent metallic element; occurs in association with zinc ores
caffeine - a bitter alkaloid found in coffee and tea that is responsible for their stimulating effects
calcification - a process that impregnates something with calcium (or calcium salts); an inflexible and unchanging state; tissue hardened by deposition of lime salts
calcitonin - thyroid hormone that tends to lower the level of calcium in the blood plasma and inhibit resorption of bone
calcium carbonate - a salt found in nature as chalk or calcite or aragonite or limestone
calcium chloride - a deliquescent salt; used in de-icing and as a drying agent
calcium phosphate - a phosphate of calcium; a main constituent of animal bones
calcium - a white metallic element that burns with a brilliant light; the fifth most abundant element in the earth's crust; an important component of most plants and animals
calculation - the procedure of calculating; determining something by mathematical or logical methods; planning something carefully and intentionally; problem solving that involves numbers or quantities
calibration - the act of checking or adjusting (by comparison with a standard) the accuracy of a measuring instrument
caliper - an instrument for measuring the distance between two points (often used in the plural); verb measure the diameter of something with calipers
calorimetry - measurement of quantities of heat
camphor - a resin obtained from the camphor tree; used in making celluloid and liniment
candela - the basic unit of luminous intensity adopted under the Systeme International d'Unites; equal to 1/60 of the luminous intensity per square centimeter of a black body radiating at the temperature of 2,046 degrees Kelvin
candida albicans - a parasitic fungus that can infect the mouth or the skin or the intestines or the vagina
candida - any of the yeastlike imperfect fungi of the genus Candida
candidiasis - an infection caused by fungi of the genus Monilia or Candida (especially Candida albicans)
canola oil - vegetable oil made from rapeseed
capillary vessel - any of the minute blood vessels connecting arterioles with venules
capillary - long and slender with a very small internal diameter; of or relating to hair; a tube of small internal diameter; holds liquid by capillary action; any of the minute blood vessels connecting arterioles with venules
capsaicin - colorless pungent crystalline compound derived from capsicum; source of the hotness of hot peppers of the genus Capsicum such as chili and cayenne and jalapeno
capsid - the outer covering of protein surrounding the nucleic acid of a virus; a variety of leaf bug
capsule - a pill in the form of a small rounded gelatinous container with medicine inside; a small container; a structure that encloses a body part; a dry dehiscent seed vessel or the spore-containing structure of e.g. mosses; a pilot's seat in an airplane that can be forcibly ejected in the case of an emergency; then the pilot descends by parachute; a spacecraft designed to transport people and support human life in outer space; a shortened version of a written work; verb enclose in a capsule; put in a short or concise form; reduce in volume
captopril - a drug (trade name Capoten) that blocks the formation of angiotensin in the kidneys resulting in vasodilation; used in the treatment of hypertension and congestive heart failure
carbamate - a salt (or ester) of carbamic acid
carbohydrate - an essential structural component of living cells and source of energy for animals; includes simple sugars with small molecules as well as macromolecular substances; are classified according to the number of monosaccharide groups they contain
carbon dioxide - a heavy odorless colorless gas formed during respiration and by the decomposition of organic substances; absorbed from the air by plants in photosynthesis
carbon monoxide - an odorless very poisonous gas that is a product of incomplete combustion of carbon
carbon tetrachloride - a colorless nonflammable liquid used as a solvent for fats and oils; because of its toxicity its use as a cleaning fluid or fire extinguisher has declined
carbon - a copy made with carbon paper; an abundant nonmetallic tetravalent element occurring in three allotropic forms: amorphous carbon and graphite and diamond; occurs in all organic compounds; a thin paper coated on one side with a dark waxy substance (often containing carbon); used to transfer characters from the original to an under sheet of paper
carbonate - a salt or ester of carbonic acid (containing the anion CO3); verb treat with carbon dioxide; turn into a carbonate
carboxyl group - the univalent radical -COOH; present in and characteristic of organic acids
carboxylic acid - an organic acid characterized by one or more carboxyl groups
carcinoma in situ - a cluster of malignant cells that has not yet invaded the deeper epithelial tissue or spread to other parts of the body
carcinoma - any malignant tumor derived from epithelial tissue; one of the four major types of cancer
carcinosarcoma - a malignant neoplasm composed of carcinoma and sarcoma extensively intermixed
cardia - the opening into the stomach and that part of the stomach connected to the esophagus
cardiac arrest - absence of systole; failure of the ventricles of the heart to contract (usually caused by ventricular fibrillation) with consequent absence of the heart beat leading to oxygen lack and eventually to death
cardiac glycoside - obtained from a number of plants and used to stimulate the heart in cases of heart failure
cardiac output - the amount of blood pumped out by the ventricles in a given period of time
cardiogenic shock - shock caused by cardiac arrest
cardiologist - a specialist in cardiology; a specialist in the structure and function and disorders of the heart
cardiomegaly - an abnormal enlargement of the heart
cardiomyopathy - a disorder (usually of unknown origin) of the heart muscle (myocardium)
cardiopulmonary resuscitation - an emergency procedure consisting of external cardiac massage and artificial respiration; the first treatment for a person who has collapsed and has no pulse and has stopped breathing; attempts to restore circulation of the blood and prevent death or brain damage due to lack of oxygen
cardiopulmonary - of or pertaining to or affecting both the heart and the lungs and their functions
cardiovascular disease - a disease of the heart or blood vessels
cardiovascular system - the organs and tissues involved in circulating blood and lymph through the body
cardiovascular - of or pertaining to or involving the heart and blood vessels
caregiver - a person who is responsible for attending to the needs of a child or dependent adult; a person who helps in identifying or preventing or treating illness or disability
carina - any of various keel-shaped structures or ridges such as that on the breastbone of a bird or that formed by the fused petals of a pea blossom; a keel-shaped constellation in the southern hemisphere; contains the start Canopus
carmine - of a color at the end of the color spectrum (next to orange); resembling the color of blood or cherries or tomatoes or rubies; a variable color averaging a vivid red; verb color carmine
carotene - yellow or orange-red fat-soluble pigments in plants; an orange isomer of an unsaturated hydrocarbon found in many plants; is converted into vitamin A in the liver
carotenoid - any of a class of highly unsaturated yellow to red pigments occurring in plants and animals
carotid artery - either of two major arteries of the neck and head; branches from the aorta
carotid body - a chemoreceptor located near the bifurcations of the carotid arteries; monitors oxygen content of the blood and helps control respiration
carpal tunnel syndrome - a painful disorder caused by compression of a nerve in the carpal tunnel; characterized by discomfort and weakness in the hands and fingers and by sensations of tingling, burning or numbness
carrageenan - a colloidal extract from carrageen seaweed and other red algae
cartilage - tough elastic tissue; mostly converted to bone in adults
case study - a detailed analysis of a person or group from a social or psychological or medical point of view; a careful study of some social unit (as a corporation or division within a corporation) that attempts to determine what factors led to its success or failure
casein - a milk protein used in making e.g. plastics and adhesives; a water-base paint made with a protein precipitated from milk
caspase - any of a group of proteases that mediate apoptosis
castor oil - a purgative extracted from the seed of the castor plant; used in paint and varnish as well as medically
castration - surgical removal of the testes or ovaries (usually to inhibit hormone secretion in cases of breast cancer in women or prostate cancer in men); neutering a male animal by removing the testicles; the deletion of objectionable parts from a literary work
cat scratch disease - a disease thought to be transmitted to humans by a scratch from a cat
catalase - enzyme found in most plant and animal cells that functions as an oxidative catalyst; decomposes hydrogen peroxide into hydrogen and water
catalepsy - a trancelike state with loss of voluntary motion and failure to react to stimuli
catalog - a book or pamphlet containing an enumeration of things; a complete list of things; usually arranged systematically; verb make an itemized list or catalog of; classify; make a catalogue, compile a catalogue
cataract - a large waterfall; violent rush of water over a precipice; clouding of the natural lens of the eye
catechin - a tannic acid that is extracted from black catechu as a white crystalline substance
catecholamine - any of a group of chemicals including epinephrine and norepinephrine that are produced in the medulla of the adrenal gland
cathartic - strongly laxative; emotionally purging (of e.g. art); emotionally purging; a purging medicine; stimulates evacuation of the bowels
catheterization - the operation of introducing a catheter into the body
cathexis - (psychoanalysis) the libidinal energy invested in some idea or person or object
cation - a positively charged ion
caudal - situated in or directed toward the part of the body from which the tail arises; resembling a tail; constituting or relating to a tail; toward the posterior end of the body
caudate nucleus - a tail-shaped basal ganglion located in a lateral ventricle of the brain
causalgia - a burning pain in a limb along the course of a peripheral nerve; usually associated with skin changes
cecum - the cavity in which the large intestine begins and into which the ileum opens
cefadroxil - a cephalosporin antibiotic (trade name Ultracef)
cefoperazone - a parenteral cephalosporin (trade name Cefobid) used for severe infections
cefotaxime - a parenteral cephalosporin (trade name Claforan) used for severe infections of the lungs or throat or ears or urinary tract
ceftazidime - a parenteral cephalosporin (trade names Fortaz and Tazicef) used to treat moderate infections
ceftriaxone - a parenteral cephalosporin (trade name Rocephin) used for severe infection of the lungs or throat or ears or urinary tract
cefuroxime - a cephalosporin that can be given parenterally (trade name Zinacef) or orally by tablets (trade name Ceftin); indicated for infections of the lungs or throat or ears or urinary tract or meninges
celecoxib - a Cox-2 inhibitor (trade name Celebrex) that relieves pain without harming the digestive tract
celiac artery - an artery that originates from the abdominal aorta just below the diaphragm and branches into the left gastric artery and the common hepatic artery and the splenic artery
celiac disease - a disorder in children and adults; inability to tolerate wheat protein (gluten); symptoms include foul-smelling diarrhea and emaciation; often accompanied by lactose intolerance
cell death - (physiology) the normal degeneration and death of living cells (as in various epithelial cells)
cell division - the process in reproduction and growth by which a cell divides to form daughter cells
cell nucleus - a part of the cell containing DNA and RNA and responsible for growth and reproduction
cell wall - a rigid layer of polysaccharides enclosing the membrane of plant and prokaryotic cells; maintains the shape of the cell and serves as a protective barrier
cell - (biology) the basic structural and functional unit of all organisms; they may exist as independent units of life (as in monads) or may form colonies or tissues as in higher plants and animals; a device that delivers an electric current as the result of a chemical reaction; a room where a prisoner is kept; small room is which a monk or nun lives; any small compartment; a small unit serving as part of or as the nucleus of a larger political movement; a hand-held mobile radiotelephone for use in an area divided into small sections, each with its own short-range transmitter/receiver
cellular respiration - the metabolic processes whereby certain organisms obtain energy from organic molecules; processes that take place in the cells and tissues during which energy is released and carbon dioxide is produced and absorbed by the blood to be transported to the lungs
cellulitis - an inflammation of body tissue (especially that below the skin) characterized by fever and swelling and redness and pain
cellulose - a polysaccharide that is the chief constituent of all plant tissues and fibers
cementum - a specialized bony substance covering the root of a tooth
centimeter - a metric unit of length equal to one hundredth of a meter
central nervous system - the portion of the vertebrate nervous system consisting of the brain and spinal cord
central - in or near a center or constituting a center; the inner area; centrally located and easy to reach; used in the description of a place that in the middle of another place; serving as an essential component; a workplace that serves as a telecommunications facility where lines from telephones can be connected together to permit communication
centrifugation - the process of separating substances by the use of a centrifuge
centriole - one of a pair of small cylindrical cell organelles near the nucleus in animal cells; composed of nine triplet microtubules and form the asters during mitosis
centromere - a specialized condensed region of each chromosome that appears during mitosis where the chromatids are held together to form an X shape
centrosome - small region of cytoplasm adjacent to the nucleus; contains the centrioles and serves to organize the microtubules
cephalexin - an oral cephalosporin (trade names Keflex and Keflin and Keftab) commonly prescribe for mild to moderately severe infections of the skin or ears or throat or lungs or urinary tract
cephaloglycin - antibiotic related to cephalosporin but no longer in common use
cephalometry - measurement of human heads
cephaloridine - a broad spectrum semisynthetic antibiotic produced by modifying cephalosporin
cephalosporin - one of several broad spectrum antibiotic substances obtained from fungi and related to penicillin (trade names Mefoxin); addition of side chains has produced semisynthetic antibiotics with greater antibacterial activity
cephalothin - a semisynthetic analogue of cephalosporin
cerebellum - a major division of the vertebrate brain; situated above the medulla oblongata and beneath the cerebrum in humans
cerebral aneurysm - an aneurysm of the carotid artery
cerebral aqueduct - a canal connecting the third and fourth ventricles
cerebral artery - any of the arteries supplying blood to the cerebral cortex
cerebral cortex - the layer of unmyelinated neurons (the grey matter) forming the cortex of the cerebrum
cerebral hemisphere - either half of the cerebrum
cerebral hemorrhage - bleeding from a ruptured blood vessel in the brain
cerebral palsy - a loss or deficiency of motor control with involuntary spasms caused by permanent brain damage present at birth
cerebral peduncle - a bundle of myelinated neurons joining different parts of the brain
cerebrospinal fluid - clear liquid produced in the ventricles of the brain; fills and protects cavities in the brain and spinal cord
cerebrovascular - of or relating to the brain and the blood vessels that supply it
cerebrum - anterior portion of the brain consisting of two hemispheres; dominant part of the brain in humans
cerium - a ductile grey metallic element of the lanthanide series; used in lighter flints; the most abundant of the rare-earth group
certification - the act of certifying or bestowing a franchise on; validating the authenticity of something or someone; a document attesting to the truth of certain stated facts; confirmation that some fact or statement is true
cerumen - a soft yellow wax secreted by glands in the ear canal
cervical - relating to or associated with the neck; of or relating to the cervix of the uterus
cervicitis - inflammation of the uterine cervix
cervix - necklike opening to the uterus; the part of an organism that connects the head to the rest of the body
cesarean section - the delivery of a fetus by surgical incision through the abdominal wall and uterus (from the belief that Julius Caesar was born that way)
cesium - a soft silver-white ductile metallic element (liquid at normal temperatures); the most electropositive and alkaline metal
cestoda - tapeworms
chaplain - a clergyman ministering to some institution
charcoal - of a very dark grey; a stick of black carbon material used for drawing; a drawing made with a stick of black carbon material; a very dark grey color; a carbonaceous material obtained by heating wood or other organic matter in the absence of air; verb draw, trace, or represent with charcoal
cheek pouch - a membranous pouch inside the mouth of many rodents (as a gopher)
cheek - either side of the face below the eyes; impudent aggressiveness; either of the two large fleshy masses of muscular tissue that form the human rump; an impudent statement; verb speak impudently to
cheilitis - inflammation and cracking of the skin of the lips
chemical - relating to or used in chemistry; of or made from or using substances produced by or used in reactions involving atomic or molecular changes; produced by or used in a reaction involving changes in atoms or molecules
chemistry - the science of matter; the branch of the natural sciences dealing with the composition of substances and their properties and reactions; the way two individuals relate to each other
chemosis - edema of the mucous membrane of the eyeball and eyelid lining
chemotaxis - movement by a cell or organism in reaction to a chemical stimulus
chemotherapy - the use of chemical agents to treat or control disease (or mental illness)
chest pain - pain in the chest
chickenpox - an acute contagious disease caused by herpes varicella zoster virus; causes a rash of vesicles on the face and body
chilblain - inflammation of the hands and feet caused by exposure to cold and moisture
child abuse - the physical or emotional or sexual mistreatment of children
child care - a service involving care for other people's children
child psychology - the branch of psychology that studies the social and mental development of children
chimera - a grotesque product of the imagination; (Greek mythology) fire-breathing female monster with a lion's head and a goat's body and a serpent's tail; daughter of Typhon
chin - the protruding part of the lower jaw; Kamarupan languages spoken in western Burma and Bangladesh and easternmost India; verb raise oneself while hanging from one's hands until one's chin is level with the support bar
chironomidae - midges
chiropractic - a method of treatment that manipulates body structures (especially the spine) to relieve low back pain or even headache or high blood pressure
chitin - a tough semitransparent horny substance; the principal component of the exoskeletons of arthropods and the cell walls of certain fungi
chlamydia trachomatis - bacteria responsible for the sexually transmitted diseases chlamydia and lymphogranuloma venereum
chlamydia - coccoid rickettsia infesting birds and mammals; cause infections of eyes and lungs and genitourinary tract; a sexually transmitted infection caused by bacteria of the genus Chlamydia
chlamydiaceae - Gram-negative parasites in warm-blooded vertebrates
chloasma - a tan discoloration of a woman's face that is associated with pregnancy or with the use of oral contraceptives
chloral hydrate - a colorless crystalline drug used as a sedative; irritates the stomach and can be addictive
chlorambucil - an alkalating agent (trade name Leukeran) used to treat some kinds of cancer
chloramphenicol - an oral antibiotic (trade name Chloromycetin) used to treat serious infections (especially typhoid fever)
chlordiazepoxide - a tranquilizer (trade names Librium and Libritabs) used in the treatment of alcoholism
chlorhexidine - a long-lasting liquid antiseptic; used by surgeons to wash their hands before performing surgery
chlorine - a common nonmetallic element belonging to the halogens; best known as a heavy yellow irritating toxic gas; used to purify water and as a bleaching agent and disinfectant; occurs naturally only as a salt (as in sea water)
chloroform - a volatile liquid haloform (CHCl3); formerly used as an anesthetic; verb anesthetize with chloroform
chlorophyll - any of a group of green pigments found in photosynthetic organisms; there are four naturally occurring forms
chloroplast - plastid containing chlorophyll and other pigments; in plants that carry out photosynthesis
chloroprene - derivative of butadiene used in making neoprene by polymerization
chloroquine - an antimalarial drug used to treat malaria and amebic dysentery and systemic lupus erythematosus
chlorothiazide - a diuretic drug (trade name Diuril) used in the treatment of edema and hypertension
chlorpromazine - a drug (trade name Thorazine) derived from phenothiazine that has antipsychotic effects and is used as a sedative and tranquilizer
chlorthalidone - a diuretic (trade names Hygroton and Thalidone) used to control hypertension and conditions that cause edema; effective in lowering blood pressure to prevent heart attacks
choke - a valve that controls the flow of air into the carburetor of a gasoline engine; a coil of low resistance and high inductance used in electrical circuits to pass direct current and attenuate alternating current; verb breathe with great difficulty, as when experiencing a strong emotion; constrict (someone's) throat and keep from breathing; reduce the air supply; be too tight; rub or press; wring the neck of; check or slow down the action or effect of; fail to perform adequately due to tension or agitation; cause to retch or choke; struggle for breath; have insufficient oxygen intake; pass from physical life and lose all bodily attributes and functions necessary to sustain life; suppress the development, creativity, or imagination of; become stultified, suppressed, or stifled; impair the respiration of or obstruct the air passage of; become or cause to become obstructed
cholangiography - roentgenographic examination of the bile ducts after a contrast medium has been injected
cholangitis - inflammation of the bile ducts
cholecystectomy - surgical removal of the gall bladder (usually for relief of gallstone pain)
cholecystitis - inflammation of the gall bladder
cholelithiasis - the presence of gallstones in the gallbladder
cholera - an acute intestinal infection caused by ingestion of contaminated water or food
cholestasis - a condition in which little or no bile is secreted or the flow of bile into the digestive tract is obstructed
cholesterol - an animal sterol that is normally synthesized by the liver; the most abundant steroid in animal tissues
choline - a B-complex vitamin that is a constituent of lecithin; essential in the metabolism of fat
chondrodystrophy - an inherited skeletal disorder beginning before birth; cartilage is converted to bone resulting in dwarfism
chondroma - a common benign tumor of cartilage cells
chondrosarcoma - a malignant neoplasm of cartilage cells
chorea - any of several degenerative nervous disorders characterized by spasmodic movements of the body and limbs; chorea in dogs
chorioallantoic membrane - very vascular fetal membrane composed of the fused chorion and adjacent wall of the allantois
chorion - outermost membranous sac enclosing the embryo in higher vertebrates (reptiles, birds and mammals)
chorioretinitis - inflammation of the choroid layer behind the retina
choroid plexus - a vascular plexus of the cerebral ventricles that regulate intraventricular pressure
choroid - a highly vascular membrane in the eye between the retina and the sclera
chromatid - one of two identical strands into which a chromosome splits during mitosis
chromatin - the readily stainable substance of a cell nucleus consisting of DNA and RNA and various proteins; during mitotic division it condenses into chromosomes
chromatography - a process used for separating mixtures by virtue of differences in absorbency
chromium - a hard brittle multivalent metallic element; resistant to corrosion and tarnishing
chromoplast - plastid containing pigments other than chlorophyll usually yellow or orange carotenoids
chromosome - a threadlike body in the cell nucleus that carries the genes in a linear order
chronic bronchitis - a form of bronchitis characterized by excess production of sputum leading to a chronic cough and obstruction of air flow
chronic gastritis - persistent gastritis can be a symptom of a gastric ulcer or pernicious anemia or stomach cancer or other disorders
chronic leukemia - slowly progressing leukemia
chronic lymphocytic leukemia - chronic leukemia characterized by lymphoblast-like cells; more common in older men
chronic - being long-lasting and recurrent or characterized by long suffering
chyle - a milky fluid consisting of lymph and emulsified fats; formed in the small intestine during digestion of ingested fats
chylomicron - a microscopic particle of triglycerides produced in the intestines during digestion; in the bloodstream they release their fatty acids into the blood
chymosin - an enzyme that occurs in gastric juice; causes milk to coagulate
cigar smoker - a smoker of cigars
ciliary body - the part of the tunic of the eye between the choroid coat and the iris
ciliophora - class of protozoa having cilia or hairlike appendages on part or all of the surface during some part of the life cycle
cilium - a hairlike projection from the surface of a cell; provides locomotion in free-swimming unicellular organisms; any of the short curved hairs that grow from the edges of the eyelids
cimetidine - a drug (trade name Tagamet) used to treat peptic ulcers by decreasing the secretion of stomach acid
ciprofloxacin - an oral antibiotic (trade name Cipro) used against serious bacterial infections of the skin or respiratory tract or urinary tract or bones or joints
circadian rhythm - a daily cycle of activity observed in many living organisms
cirrhosis - a chronic disease interfering with the normal functioning of the liver; the major cause is chronic alcoholism
citrulline - an amino acid that does not occur in proteins but is an intermediate in the conversion of ornithine to arginine
class bivalvia - oysters; clams; scallops; mussels
classification - restriction imposed by the government on documents or weapons that are available only to certain authorized people; the basic cognitive process of arranging into classes or categories; a group of people or things arranged by class or category; the act of distributing things into classes or categories of the same type
claustrophobia - a morbid fear of being closed in a confined space
clavicle - bone linking the scapula and sternum
cleft lip - a congenital cleft in the middle of the upper lip
cleft palate - a congenital fissure of the hard palate
clinical - scientifically detached; unemotional; relating to a clinic or conducted in or as if in a clinic and depending on direct observation of patients
clinician - a practitioner (of medicine or psychology) who does clinical work instead of laboratory experiments
clioquinol - drug used to treat certain fungal infection (as athlete's foot)
clitoris - a female sexual organ homologous to the penis
clofibrate - a drug (trade name Atromid-S) that reduces lipids in the blood serum; used to treat some cardiovascular diseases
clomiphene - a fertility drug (trade name Clomid) that is used to stimulate ovulation and that has been associated with multiple births
clomipramine - a tricyclic antidepressant drug
clone - a group of genetically identical cells or organisms derived from a single cell or individual by some kind of asexual reproduction; an unauthorized copy or imitation; a person who is almost identical to another; verb make multiple identical copies of
clonidine - an antihypertensive (trade name Catapres) that can be administered orally or via transdermal patches
cloning - a general term for the research activity that creates a copy of some biological entity (a gene or organism or cell)
clonus - convulsion characterized by alternating contractions and relaxations
clostridium botulinum - anaerobic bacterium producing botulin the toxin that causes botulism
clostridium perfringens - anaerobic Gram-positive rod bacterium that produces epsilon toxin; can be used as a bioweapon
clostridium - spindle-shaped bacterial cell especially one swollen at the center by an endospore
clotting factor - any of the factors in the blood whose actions are essential for blood coagulation
clove oil - essential oil obtained from cloves and used to flavor medicines
clozapine - an antipsychotic drug (trade name Clozaril) used as a sedative and for treatment-resistant schizophrenia; know to have few side effects
cluster headache - a painful recurring headache associated with the release of histamine from cells
cnidaria - hydras; polyps; jellyfishes; sea anemones; corals
coal tar - a tar formed from distillation of bituminous coal; coal tar can be further distilled to give various aromatic compounds
coal - fossil fuel consisting of carbonized vegetable matter deposited in the Carboniferous period; a hot fragment of wood or coal that is left from a fire and is glowing or smoldering; verb take in coal; supply with coal; burn to charcoal
cobalt - a hard ferromagnetic silver-white bivalent or trivalent metallic element; a trace element in plant and animal nutrition
cocaine - a narcotic (alkaloid) extracted from coca leaves; used as a surface anesthetic or taken for pleasure; can become powerfully addictive
coccidia - an order in the subclass Telosporidia
coccidioidomycosis - an infection of the lungs and skin characterized by excessive sputum and nodules
coccidiosis - (veterinary medicine) infestation with coccidia
coccyx - the end of the vertebral column in humans and tailless apes
cochlea - the snail-shaped tube (in the inner ear coiled around the modiolus) where sound vibrations are converted into nerve impulses by the organ of Corti
coconut oil - oil from coconuts
codeine - derivative of opium; used as an antitussive (to relieve coughing) and an analgesic (to relive pain)
codon - a specific sequence of three adjacent bases on a strand of DNA or RNA that provides genetic code information for a particular amino acid
coenzyme a - a coenzyme present in all living cells; essential to metabolism of carbohydrates and fats and some amino acids
coenzyme - a small molecule (not a protein but sometimes a vitamin) essential for the activity of some enzymes
cognition - the psychological result of perception and learning and reasoning
coitus interruptus - a method of birth control in which coitus is initiated but the penis is deliberately withdrawn before ejaculation
coitus - the act of sexual procreation between a man and a woman; the man's penis is inserted into the woman's vagina and excited until orgasm and ejaculation occur
coliphage - a bacteriophage that infects the bacterium Escherichia coli
colitis - inflammation of the colon
collagen - a fibrous scleroprotein in bone and cartilage and tendon and other connective tissue; yields gelatin on boiling
collagenase - any enzyme that catalyzes the hydrolysis of collagen and gelatin
collodion - a colorless syrupy solution of pyroxylin in ether and alcohol; used as a coating for wounds or photographic films
colloid - a mixture with properties between those of a solution and fine suspension
colon - the part of the large intestine between the cecum and the rectum; it extracts moisture from food residues before they are excreted; a punctuation mark (:) used after a word introducing a series or an example or an explanation (or after the salutation of a business letter); a port city at the Caribbean entrance to the Panama Canal; the basic unit of money in Costa Rica; equal to 100 centimos; the basic unit of money in El Salvador; equal to 100 centavos
colonoscope - an elongated fiberoptic endoscope for examining the entire colon from cecum to rectum
colonoscopy - visual examination of the colon (with a colonoscope) from the cecum to the rectum; requires sedation
color blindness - genetic inability to distinguish differences in hue
color vision - the normal ability to see colors
color - having or capable of producing colors; the appearance of objects (or light sources) described in terms of a person's perception of their hue and lightness (or brightness) and saturation; a visual attribute of things that results from the light they emit or transmit or reflect; the timbre of a musical sound; interest and variety and intensity; (physics) the characteristic of quarks that determines their role in the strong interaction; each flavor of quarks comes in three colors; a race with skin pigmentation different from the white race (especially Blacks); an outward or token appearance or form that is deliberately misleading; any material used for its color; verb add color to; gloss or excuse; decorate with colors; modify or bias; change color, often in an undesired manner; affect as in thought or feeling
colorectal - relating to or affecting the colon and the rectum
colorimetry - quantitative chemical analysis by color using a colorimeter
colostomy - a surgical operation that creates an opening from the colon to the surface of the body to function as an anus
colostrum - milky fluid secreted for the first day or two after parturition
coma - a state of deep and often prolonged unconsciousness; usually the result of disease or injury; (astronomy) the luminous cloud of particles surrounding the frozen nucleus of a comet; forms as the comet approaches the sun and is warmed; a usually terminal tuft of hairs especially on a seed
comedo - a black-tipped plug clogging a pore of the skin
common bile duct - a duct formed by the hepatic and cystic ducts; opens into the duodenum
common cold - a mild viral infection involving the nose and respiratory passages (but not the lungs)
common wart - a benign growth (often with a rough surface)
community - (ecology) a group of interdependent organisms inhabiting the same region and interacting with each other; a group of people living in a particular local area; a group of people having ethnic or cultural or religious characteristics in common; a group of nations having common interests; common ownership; agreement as to goals; the body of people in a learned occupation; a district where people live; occupied primarily by private residences
comparative anatomy - the study of anatomical features of animals of different species
complementary dna - single-stranded DNA that is complementary to messenger RNA or DNA that has been synthesized from messenger RNA by reverse transcriptase
complication - the act or process of complicating; a development that complicates a situation; a situation or condition that is complex or confused; any disease or disorder that occurs during the course of (or because of) another disease; puzzling complexity
composition - something that is created by arranging several things to form a unified whole; the spatial property resulting from the arrangement of parts in relation to each other and to the whole; an essay (especially one written as an assignment); a mixture of ingredients; the act of creating written works; musical creation; the way in which someone or something is composed; art and technique of printing with movable type; a musical work that has been created
comprehension - an ability to understand the meaning or importance of something (or the knowledge acquired as a result); the relation of comprising something
compression bandage - bandage that stops the flow of blood from an artery by applying pressure
compression fracture - fracture in which the bone collapses (especially in short bones such as vertebrae)
conception - the act of becoming pregnant; fertilization of an ovum by a spermatozoon; the creation of something in the mind; an abstract or general idea inferred or derived from specific instances; the event that occurred at the beginning of something
concern - something that interests you because it is important or affects you; something or someone that causes anxiety; a source of unhappiness; a feeling of sympathy for someone or something; an anxious feeling; a commercial or industrial enterprise and the people who constitute it; verb be on the mind of; have to do with or be relevant to
condition - the procedure that is varied in order to estimate a variable's effect by comparison with a control condition; an assumption on which rests the validity or effect of something else; (usually plural) a statement of what is required as part of an agreement; a mode of being or form of existence of a person or thing; a state at a particular time; the state of (good) health (especially in the phrases `in condition' or `in shape' or `out of condition' or `out of shape'); information that should be kept in mind when making a decision; verb apply conditioner to in order to make smooth and shiny; put into a better state; establish a conditioned response; specify as a condition or requirement in a contract or agreement; make an express demand or provision in an agreement; train by instruction and practice; especially to teach self-control
conditional - imposing or depending on or containing a condition; qualified by reservations
conditioning - a learning process in which an organism's behavior becomes dependent on the occurrence of a stimulus in its environment
conduction anesthesia - anesthesia of an area supplied by a nerve; produced by an anesthetic agent applied to the nerve
conductive hearing loss - hearing loss due to problems with the bones of the middle ear
condyloma acuminatum - a small benign wart on or around the genitals and anus
confidentiality - discretion in keeping secret information; the state of being secret
conformation - a symmetrical arrangement of the parts of a thing; acting according to certain accepted standards; any spatial attributes (especially as defined by outline)
confusion - a mistake that results from taking one thing to be another; an act causing a disorderly combination of elements with identities lost and distinctions blended; a mental state characterized by a lack of clear and orderly thought and behavior; a feeling of embarrassment that leaves you confused; disorder resulting from a failure to behave predictably
congenital abnormality - a defect that is present at birth
congenital megacolon - congenital condition in which the colon does not have the normal network of nerves; there is little urge to defecate so the feces accumulate and cause megacolon
congestive heart failure - inability to pump enough blood to avoid congestion in the tissues
congo red - a red-brown azo dye especially as a chemical pH indicator (congo red is red in basic and blue in acidic solutions)
conjunctiva - a transparent membrane covering the eyeball and under surface of the eyelid
conjunctivitis - inflammation of the conjunctiva of the eye
conn's syndrome - disturbances in saltwater balance and symptoms of weakness and muscular cramps and twitching and convulsions and sometimes paralysis; usually caused by a benign tumor of the cortex of the adrenal gland that leads to excess secretion of aldosterone
connective tissue - tissue of mesodermal origin consisting of e.g. collagen fibroblasts and fatty cells; supports organs and fills spaces between them and forms tendons and ligaments
consciousness - an alert cognitive state in which you are aware of yourself and your situation; having knowledge of
consistency - a harmonious uniformity or agreement among things or parts; (logic) an attribute of a logical system that is so constituted that none of the propositions deducible from the axioms contradict one another; the property of holding together and retaining its shape; logical coherence and accordance with the facts
constipation - irregular and infrequent or difficult evacuation of the bowels; can be a symptom of intestinal obstruction or diverticulitis; the act of making something futile and useless (as by routine)
consultation - a conference between two or more people to consider a particular question; a conference (usually with someone important); the act of referring or consulting
contact dermatitis - a delayed type of allergic reaction of the skin resulting from skin contact with a specific allergen (such as poison ivy)
contact lens - a thin curved glass or plastic lens designed to fit over the cornea in order to correct vision or to deliver medication
contraception - birth control by the use of devices (diaphragm or intrauterine device or condom) or drugs or surgery
contraceptive device - an agent or device intended to prevent conception
contract - a variety of bridge in which the bidder receives points toward game only for the number of tricks he bid; a binding agreement between two or more persons that is enforceable by law; (contract bridge) the highest bid becomes the contract setting the number of tricks that the bidder must make; verb be stricken by an illness, fall victim to an illness; enter into a contractual arrangement; make smaller; become smaller or draw together; reduce in scope while retaining essential elements; make or become more narrow or restricted; compress or concentrate; squeeze or press together; engage by written agreement
contracture - an abnormal and usually permanent contraction of a muscle
contraindication - (medicine) a reason that makes it inadvisable to prescribe a particular drug or employ a particular procedure or treatment
contralateral - on or relating to the opposite side (of the body)
contrast medium - a substance that is opaque to x-rays; when administered it allows a radiologist to examine the organ or tissue it fills
contusion - the action of bruising; an injury that doesn't break the skin but results in some discoloration
coping - brick that is laid sideways at the top of a wall
copolymer - a polymer consisting of two or more different monomers
copper - any of various small butterflies of the family Lycaenidae having coppery wings; a reddish-brown color resembling the color of polished copper; a copper penny; a ductile malleable reddish-brown corrosion-resistant diamagnetic metallic element; occurs in various minerals but is the only metal that occurs abundantly in large masses; used as an electrical and thermal conductor; uncomplimentary terms for a policeman; verb coat with a layer of copper
coprophagy - eating feces; in human a symptom of some kinds of insanity
corn oil - oil from the germs of corn grains
cornea - transparent anterior portion of the outer covering of the eye; it covers the lens and iris and is continuous with the sclera
coronary artery disease - a stage of arteriosclerosis involving fatty deposits (atheromas) inside the arterial walls
coronary artery - the artery that branches from the aorta to supply blood to the heart
coronary sinus - a short sinus receiving most of the veins of the heart; empties into the right atrium
coronary - surrounding like a crown (especially of the blood vessels surrounding the heart); obstruction of blood flow in a coronary artery by a blood clot (thrombus)
corpus callosum - a broad transverse nerve tract connecting the two cerebral hemispheres
corpus luteum - yellow endocrine tissue that forms in a ruptured Graafian follicle following the release of an ovum
corpus striatum - a striped mass of white and grey matter located in front of the thalamus in each cerebral hemisphere; consists of the caudate nucleus and the lenticular nucleus
corticosteroid - a steroid hormone produced by the adrenal cortex or synthesized; administered as drugs they reduce swelling and decrease the body's immune response
corticosterone - secreted by the adrenal cortex; involved in regulating water and electrolyte balance in the body
corticotropin - a hormone produced by the anterior pituitary gland that stimulates the adrenal cortex
cortisol - an adrenal-cortex hormone (trade names Hydrocortone or Cortef) that is active in carbohydrate and protein metabolism
cortisone - a corticosteroid hormone (trade name Cortone Acetate) normally produced by the adrenal cortex; is converted to hydrocortisone
corynebacterium diphtheriae - a species of bacterium that causes diphtheria
corynebacterium - any species of the genus Corynebacterium
cottonseed oil - edible oil pressed from cottonseeds
cough - the act of exhaling air suddenly with a noise; sudden expulsion of air from the lungs that clears the air passages; a common symptom of upper respiratory infection or bronchitis or pneumonia or tuberculosis; verb exhale abruptly, as when one has a chest cold or congestion
coulomb - French physicist famous for his discoveries in the field of electricity and magnetism; formulated Coulomb's Law (1736-1806); a unit of electrical charge equal to the amount of charge transferred by a current of 1 ampere in 1 second
counseling - something that provides direction or advice as to a decision or course of action
count - the act of counting; a nobleman (in various countries) having rank equal to a British earl; the total number counted; verb include as if by counting; have faith or confidence in; name or recite the numbers; determine the number or amount of; have weight; have import, carry weight; put into a group; take account of; show consideration for; take into account
coxsackie virus - enterovirus causing a disease resembling poliomyelitis but without paralysis
cranial cavity - the cavity enclosed by the cranium
cranial nerve - any of the 12 paired nerves that originate in the brain stem
cranial - of or relating to the cranium which encloses the brain
craniotomy - a surgical opening through the skull
craving - an intense desire for some particular thing
cream - toiletry consisting of any of various substances in the form of a thick liquid that have a soothing and moisturizing effect when applied to the skin; the part of milk containing the butterfat; the best people or things in a group; verb add cream to one's coffee, for example; put on cream, as on one's face or body; beat thoroughly and conclusively in a competition or fight; make creamy by beating; remove from the surface
creatine - an amino acid that does not occur in proteins but is found in the muscle tissue of vertebrates both in the free form and as phosphocreatine; supplies energy for muscle contraction
creativity - the ability to create
crisis intervention - psychotherapy that focuses on acute critical situations (depressive episodes or attempted suicides or drug overdoses) with the aim of restoring the person to the level of functioning before the crisis
crohn's disease - a serious chronic and progressive inflammation of the ileum producing frequent bouts of diarrhea with abdominal pain and nausea and fever and weight loss
croton oil - viscid acrid brownish-yellow oil from the seeds of Croton tiglium having a violent cathartic action
croup - a disease of infants and young children; harsh coughing and hoarseness and fever and difficult breathing; the part of a quadruped that corresponds to the human buttocks
crown - the part of a hat (the vertex) that covers the crown of the head; an ornamental jewelled headdress signifying sovereignty; a wreath or garland worn on the head to signify victory; the center of a cambered road; the part of a tooth above the gum that is covered with enamel; the Crown (or the reigning monarch) as the symbol of the power and authority of a monarchy; the upper branches and leaves of a tree; an English coin worth 5 shillings; the top of the head; the award given to the champion; the top point of a mountain or hill; verb be the culminating event; put an enamel cover on; invest with regal power; enthrone; form the topmost part of
crutch - anything that serves as an expedient; a wooden or metal staff that fits under the armpit and reaches to the ground; used by disabled person while walking
crying - conspicuously and outrageously bad or reprehensible; noisy with or as if with loud cries and shouts; demanding attention; the process of shedding tears (usually accompanied by sobs or other inarticulate sounds)
cryostat - a thermostat that operates at very low temperatures
cryosurgery - the use of extreme cold (usually liquid nitrogen) to destroy unwanted tissue (warts or cataracts or skin cancers)
cryptococcosis - a fungal infection characterized by nodular lesions--first in the lungs and spreading to the nervous system
cryptorchidism - failure of one or both testes to move into the scrotum as the male fetus develops
cubic millimeter - a metric measure of volume or capacity equal to a cube 1 millimeter on each edge
cue - sports implement consisting of a tapering rod used to strike a cue ball in pool or billiards; an actor's line that immediately precedes and serves as a reminder for some action or speech; a stimulus that provides information about what to do; evidence that helps to solve a problem; verb assist (somebody acting or reciting) by suggesting the next words of something forgotten or imperfectly learned
culdoscopy - endoscopic examination of a woman's pelvic organs by the insertion of a culdoscope through the vagina
culicidae - mosquitoes
curare - a toxic alkaloid found in certain tropical South American trees that is a powerful relaxant for striated muscles
cure - a medicine or therapy that cures disease or relieve pain; verb prepare by drying, salting, or chemical processing in order to preserve; be or become preserved; make (substances) hard and improve their usability; provide a cure for, make healthy again
curette - a surgical instrument shaped like a scoop to remove tissue from a bodily cavity
curie - French chemist (born in Poland) who won two Nobel prizes; one (with her husband and Henri Becquerel) for research on radioactivity and another for her discovery of radium and polonium (1867-1934); French physicist; husband of Marie Curie (1859-1906); a unit of radioactivity equal to the amount of a radioactive isotope that decays at the rate of 37,000,000,000 disintegrations per second
cushing's syndrome - a glandular disorder caused by excessive cortisol
cuspid - one of the four pointed conical teeth (two in each jaw) located between the incisors and the premolars
cyanosis - a bluish discoloration of the skin and mucous membranes; a sign that oxygen in the blood is dangerously diminished (as in carbon monoxide poisoning)
cyclic neutropenia - neutropenia that occurs periodically
cycloserine - an antibiotic that is especially active against the tubercle bacillus
cyclothymic disorder - a mild bipolar disorder that persists over a long time
cyclotron - an accelerator that imparts energies of several million electron-volts to rapidly moving particles
cyproheptadine - an antihistamine (trade name Periactin) used to treat some allergic reactions
cyst - a closed sac that develops abnormally in some body structure; a small anatomically normal sac or bladderlike structure (especially one containing fluid)
cysteine - an amino acid containing sulfur that is found in most proteins; oxidizes on exposure to air to form cystine
cystic fibrosis - the most common congenital disease; the child's lungs and intestines and pancreas become clogged with thick mucus; caused by defect in a single gene; there is no cure
cystine - a crystalline amino acid found in proteins (especially keratin); discovered in bladder stones
cystitis - inflammation of the urinary bladder and ureters
cytidine - a nucleoside component of DNA; composed of cytosine and deoxyribose
cytochrome - (biochemistry) a class of hemoprotein whose principle biological function is electron transfer (especially in cellular respiration)
cytogenetics - the branch of biology that studies the cellular aspects of heredity (especially the chromosomes)
cytokine - any of various proteins secreted by cells of the immune system that serve to regulate the immune system
cytokinesis - organic process consisting of the division of the cytoplasm of a cell following karyokinesis bringing about the separation into two daughter cells
cytology - the branch of biology that studies the structure and function of cells
cytolysis - pathological breakdown of cells by the destruction of their outer membrane
cytomegalovirus - any of a group of herpes viruses that enlarge epithelial cells and can cause birth defects; can affect humans with impaired immunological systems
cytopenia - a deficiency of some cellular element of the blood
cytoplasm - the protoplasm of a cell excluding the nucleus; is full of proteins that control cell metabolism
cytosine - a base found in DNA and RNA and derived from pyrimidine; pairs with guanine
cytoskeleton - a microscopic network of actin filaments and microtubules in the cytoplasm of many living cells that gives the cell shape and coherence
cytotoxicity - the degree to which something is toxic to living cells
dacryocystitis - inflammation of the lacrimal sac causing obstruction of the tube draining tears into the nose
dapsone - antibacterial drug used to treat leprosy and some kinds of skin diseases
dark adaptation - the process of adjusting the eyes to low levels of illumination; cones adapt first; rods continue to adapt for up to four hours
de novo - from the beginning
deafness - partial or complete loss of hearing
death - the act of killing; the event of dying or departure from life; the personification of death; the permanent end of all life functions in an organism or part of an organism; the absence of life or state of being dead; the time at which life ends; continuing until dead; the time when something ends; a final state
debridement - surgical removal of foreign material and dead tissue from a wound in order to prevent infection and promote healing
decanoic acid - a fatty acid found in animal oils and fats; has an unpleasant smell resembling goats
decapitation - killing by cutting off the head; execution by cutting off the victim's head
decibel - a logarithmic unit of sound intensity; 10 times the logarithm of the ratio of the sound intensity to some reference intensity
decidua - the epithelial tissue of the endometrium
deciduous tooth - one of the first temporary teeth of a young mammal (one of 20 in children)
decision making - the cognitive process of reaching a decision
decontamination - the removal of contaminants
defecation - the elimination of fecal waste through the anus
defense mechanism - (psychiatry) an unconscious process that tries to reduce the anxiety associated with instinctive desires
defibrillator - an electronic device that administers an electric shock of preset voltage to the heart through the chest wall in an attempt to restore the normal rhythm of the heart during ventricular fibrillation
degenerative disorder - condition leading to progressive loss of function
deglutition - the act of swallowing
dehydration - the process of extracting moisture; depletion of bodily fluids; dryness resulting from the removal of water
deja vu - the experience of thinking that a new situation had occurred before
delavirdine - a non-nucleoside reverse transcriptase inhibitor (trade name Rescriptor) used to treat AIDS and HIV
delirium - a usually brief state of excitement and mental confusion often accompanied by hallucinations; state of violent mental agitation
deltoid - of a leaf shape; suggesting a capital delta, with a point at the apex; a large triangular muscle covering the shoulder joint and serving to abduct and flex and extend and rotate the arm
delusion - the act of deluding; deception by creating illusory ideas; a mistaken or unfounded opinion or idea; (psychology) an erroneous belief that is held in the face of evidence to the contrary
delusional disorder - any mental disorder in which delusions play a significant role
dementia - mental deterioration of organic or functional origin
demulcent - having a softening or soothing effect especially to the skin; a medication (in the form of an oil or salve etc.) that soothes inflamed or injured skin
demyelination - loss of the myelin covering of some nerve fibers resulting in their impaired function
dendrite - short fiber that conducts toward the cell body of the neuron
dengue - an infectious disease of the tropics transmitted by mosquitoes and characterized by rash and aching head and joints
denial - the act of asserting that something alleged is not true; the act of refusing to comply (as with a request); (psychiatry) a defense mechanism that denies painful thoughts; renunciation of your own interests in favor of the interests of others; a defendant's answer or plea denying the truth of the charges against him
denominator - the divisor of a fraction
densitometer - a measuring instrument for determining optical or photographic density; a measuring instrument for determining density or specific gravity
densitometry - measuring the optical density of a substance by shining light on it and measuring its transmission
density - the amount per unit size; the spatial property of being crowded together
dental amalgam - an alloy of mercury with another metal (usually silver) used by dentists to fill cavities in teeth; except for iron and platinum all metals dissolve in mercury and chemists refer to the resulting mercury mixtures as amalgams
dental caries - soft decayed area in a tooth; progressive decay can lead to the death of a tooth
dental implant - an implant that replaces a natural tooth
dental plaque - a film of mucus and bacteria deposited on the teeth that encourages the development of dental caries
dental procedure - a procedure employed by a dentist
dentifrice - a substance for cleaning the teeth; applied with a toothbrush
dentin - bone (calcified tissue) surrounding the pulp cavity of a tooth; a calcareous material harder and denser than bone that comprises the bulk of a tooth
dentistry - the branch of medicine dealing with the anatomy and development and diseases of the teeth
dentition - the kind and number and arrangement of teeth (collectively) in a person or animal; the eruption through the gums of baby teeth
denture - a dental appliance that artificially replaces missing teeth
deoxycytidine - a nucleoside component of DNA; composed of cytosine and deoxyribose
deoxyguanosine - a nucleoside component of DNA; composed of guanine and deoxyribose
deoxyribonucleic acid - (biochemistry) a long linear polymer found in the nucleus of a cell and formed from nucleotides and shaped like a double helix; associated with the transmission of genetic information
depersonalization - representing a human being as a physical thing deprived of personal qualities or individuality; (existentialism) a loss of personal identity; a feeling of being an anonymous cog in a stupid social machine; emotional dissociative disorder in which there is loss of contact with your own personal reality accompanied by feelings of unreality and strangeness
depression - pushing down; sad feelings of gloom and inadequacy; angular distance below the horizon (especially of a celestial object); a concavity in a surface produced by pressing; a mental state characterized by a pessimistic sense of inadequacy and a despondent lack of activity; a long-term economic state characterized by unemployment and low prices and low levels of trade and investment; a period during the 1930s when there was a worldwide economic depression and mass unemployment; a sunken or depressed geological formation; a state of depression and anhedonia so severe as to require clinical intervention; an air mass of lower pressure; often brings precipitation
depressive disorder - a state of depression and anhedonia so severe as to require clinical intervention
dermabrasion - removal of scars or tattoos by anesthetizing the skin surface and then sanding or scraping off some of the outer skin layer
dermatitis - inflammation of the skin; skin becomes itchy and may develop blisters
dermatologist - a doctor who specializes in the physiology and pathology of the skin
dermatomycosis - fungal infection of the skin (especially of moist parts covered by clothing)
dermatomyositis - myositis characterized by weakness of limb and neck muscles and much muscle pain and selling accompanied by skin rash affecting cheeks and eyelids and neck and chest and limbs; progression and severity vary among individuals
dermis - the deep vascular inner layer of the skin
dermoid cyst - a cystic tumor (usually benign) with a wall lined with epithelium and a cavity containing other material
descending colon - the part of the large intestine that descends from the transverse colon to the sigmoid colon
detached - used of buildings; standing apart from others; no longer connected or joined; not fixed in position; being or feeling set or kept apart from others; showing lack of emotional involvement
detergent - having cleansing power; a cleansing agent that differs from soap but can also emulsify oils and hold dirt in suspension; a surface-active chemical widely used in industry and laundering
deuterium oxide - water containing a substantial proportion of deuterium atoms, used in nuclear reactors
deuterium - an isotope of hydrogen which has one neutron (as opposed to zero neutrons in hydrogen)
developmental psychology - the branch of psychology that studies the social and mental development of children
dexamethasone - a corticosteroid drug (trade names Decadron or Dexamethasone Intensol or Dexone or Hexadrol or Oradexon) used to treat allergies or inflammation
dextrocardia - abnormal condition where the heart is located toward the right side of the chest
diabetes insipidus - a rare form of diabetes resulting from a deficiency of vasopressin (the pituitary hormone that regulates the kidneys); characterized by the chronic excretion of large amounts of pale dilute urine which results in dehydration and extreme thirst
diabetes mellitus - diabetes caused by a relative or absolute deficiency of insulin and characterized by polyuria
diagnosis - identifying the nature or cause of some phenomenon
diagnostic procedure - a procedure followed in making a medical diagnosis
diakinesis - the final stage of the prophase of meiosis
dialyzer - a medical instrument for separating substances in solution by unequal diffusion through semipermeable membranes
diamine - any organic compound containing two amino groups
diapedesis - passage of blood cells (especially white blood cells) through intact capillary walls and into the surrounding tissue
diaper rash - dermatitis of the thighs and buttocks of infants; supposedly caused by ammonia in the urine in the child's diapers
diaphoretic - inducing perspiration; used to produce perspiration
diaphragm - a mechanical device in a camera that controls size of aperture of the lens; electro-acoustic transducer that vibrates to receive or produce sound waves; a contraceptive device consisting of a flexible dome-shaped cup made of rubber or plastic; it is filled with spermicide and fitted over the uterine cervix; (anatomy) a muscular partition separating the abdominal and thoracic cavities; functions in respiration
diaphragmatic hernia - hernia resulting from the protrusion of part of the stomach through the diaphragm
diaphysis - the main (mid) section of a long bone
diarrhea - frequent and watery bowel movements; can be a symptom of infection or food poisoning or colitis or a gastrointestinal tumor
diastole - the widening of the chambers of the heart between two contractions when the chambers fill with blood
diathermy - a method of physical therapy that involves generating local heat in body tissues by high-frequency electromagnetic currents
diatomaceous earth - a light soil consisting of siliceous diatom remains and often used as a filtering material
diazepam - a tranquilizer (trade name Valium) used to relieve anxiety and relax muscles; acts by enhancing the inhibitory actions of the neurotransmitter GABA; can also be used as an anticonvulsant drug in cases of nerve agent poisoning
diazoxide - vasodilator (trade name Hyperstat) used to treat severe hypertension
dibucaine - a local anesthetic that is administered by injection
diclofenac sodium - a nonsteroidal anti-inflammatory drug (trade name Voltaren) that is administered only orally
dicloxacillin - antibacterial (trade name Dynapen) used to treat staphylococcal infections that are resistant to penicillin
dicumarol - an anticoagulant drug that has now been largely replaced by warfarin
diencephalon - the posterior division of the forebrain; connects the cerebral hemispheres with the mesencephalon
diestrus - (of animals having several estrous cycles in one breeding season) a state or interval of sexual inactivity or quiescence between periods of activity
diet - the act of restricting your food intake (or your intake of particular foods); the usual food and drink consumed by an organism (person or animal); a prescribed selection of foods; a legislative assembly in certain countries (e.g., Japan); verb eat sparingly, for health reasons or to lose weight; follow a regimen or a diet, as for health reasons
dietetics - the scientific study of food preparation and intake
diethylstilbestrol - a potent estrogen used in medicine and in feed for livestock and poultry
dietician - a specialist in the study of nutrition
diffuse - spread out; not concentrated in one place; lacking conciseness; (of light) transmitted from a broad light source or reflected; verb move outward; cause to become widely known; spread or diffuse through
diflunisal - nonsteroidal anti-inflammatory (trade name Dolobid) used to treat arthritis and other inflammatory conditions
digestion - learning and coming to understand ideas and information; the organic process by which food is converted into substances that can be absorbed into the body; the process of decomposing organic matter (as in sewage) by bacteria or by chemical action or heat
digitoxin - digitalis preparation used to treat congestive heart failure or cardiac arrhythmia
digoxin - digitalis preparation (trade name Lanoxin) used to treat congestive heart failure or cardiac arrhythmia; helps the heart beat more forcefully
dilatation - the state of being stretched beyond normal dimensions; the act of expanding an aperture
dilation - the act of expanding an aperture; a lengthy discussion (spoken or written) on a particular topic
dilator - a surgical instrument that is used to dilate or distend an opening or an organ; a drug that causes dilation; a muscle or nerve that dilates or widens a body part
diltiazem - a calcium blocker (trade name Cardizem) used in treating hypertension or angina or heart failure
dimenhydrinate - antihistamine and antiemetic (trade name Dramamine) used to treat motion sickness
dioxin - any of several toxic or carcinogenic hydrocarbons that occur as impurities in herbicides
diphtheria - acute contagious infection caused by the bacterium Corynebacterium diphtheriae; marked by the formation of a false membrane in the throat and other air passages causing difficulty in breathing
diploidy - the condition of being diploid
diplopia - visual impairment in which an object is seen as two objects
diptera - a large order of insects having a single pair of wings and sucking or piercing mouths; includes true flies and mosquitoes and gnats and crane flies
disability - the condition of being unable to perform as a consequence of physical or mental unfitness
disaccharide - any of a variety of carbohydrates that yield two monosaccharide molecules on complete hydrolysis
disease - an impairment of health or a condition of abnormal functioning
disinfectant - preventing infection by inhibiting the growth or action of microorganisms; an agent (as heat or radiation or a chemical) that destroys microorganisms that might carry disease
dislocation - the act of disrupting an established order so it fails to continue; an event that results in a displacement or discontinuity; a displacement of a part (especially a bone) from its normal position (as in the shoulder or the vertebral column)
disruption - the act of causing disorder; an act of delaying or interrupting the continuity; an event that results in a displacement or discontinuity; a disorderly outburst or tumult
dissection - cutting so as to separate into pieces; detailed critical analysis or examination one part at a time (as of a literary work); a minute and critical analysis
disseminate - verb cause to become widely known
dissociative disorder - dissociation so severe that the usually integrated functions of consciousness and perception of self break down
distal - situated farthest from point of attachment or origin, as of a limb or bone; directed away from the midline or mesial plane of the body
distress - the seizure and holding of property as security for payment of a debt or satisfaction of a claim; psychological suffering; extreme physical pain; a state of adversity (danger or affliction or need); verb cause mental pain to
disulfiram - a drug (trade name Antabuse) used in the treatment of alcoholism; causes nausea and vomiting if alcohol is ingested
diuresis - increased secretion of urine; if not due to increased liquid intake or to the action of a diuretic drug it can be a symptom of diabetes mellitus
diuretic - any substance that tends to increase the flow of urine
diverticulitis - inflammation of a diverticulum in the digestive tract (especially the colon); characterized by painful abdominal cramping and fever and constipation
diverticulosis - presence of multiple diverticula in the walls of the colon
diverticulum - a herniation through the muscular wall of a tubular organ (especially the colon)
divorce - the legal dissolution of a marriage; verb get a divorce; formally terminate a marriage; part; cease or break association with
dizygotic twin - either of two twins who developed from two separate fertilized eggs
dizziness - a reeling sensation; a feeling that you are about to fall
docosahexaenoic acid - an omega-3 fatty acid with 22 carbon atoms; found in fish (especially tuna and bluefish)
document - anything serving as a representation of a person's thinking by means of symbolic marks; writing that provides information (especially information of an official nature); a written account of ownership or obligation; (computer science) a computer file that contains text (and possibly formatting instructions) using seven-bit ASCII characters; verb support or supply with references; record in detail
domestic violence - violence or physical abuse directed toward your spouse or domestic partner; usually violence by men against women
dominant - exercising influence or control; (of genes) producing the same phenotype whether its allele is identical or dissimilar; (music) the fifth note of the diatonic scale; an allele that produces the same phenotype whether its paired allele is identical or different
dopa - amino acid that is formed in the liver and converted into dopamine in the brain
dopamine - a monoamine neurotransmitter found in the brain and essential for the normal functioning of the central nervous system; as a drug (trade names Dopastat and Intropin) it is used to treat shock and hypotension
dorsal - belonging to or on or near the back or upper surface of an animal or organ or part; facing away from the axis of an organ or organism
dosage - the quantity of an active agent (substance or radiation) taken in or absorbed at any one time
douche - irrigation with a jet of water or medicated solution into or around a body part (especially the vagina) to treat infections or cleanse from odorous contents; a small syringe with detachable nozzles; used for vaginal lavage and enemas; verb direct a spray of water into a bodily cavity, for cleaning
doxepin - a tricyclic antidepressant (trade names Adapin and Sinequan) with numerous side effects (dry mouth and sedation and gastrointestinal disturbances)
doxorubicin - an antibiotic used as an anticancer drug
doxycycline - an antibiotic derived from tetracycline that is effective against many infections
dracunculiasis - a painful and debilitating infestation contracted by drinking stagnant water contaminated with Guinea worm larvae that can mature inside a human's abdomen until the worm emerges through a painful blister in the person's skin
dracunculus medinensis - parasitic roundworm of India and Africa that lives in the abdomen or beneath the skin of humans and other vertebrates
drainage - emptying something accomplished by allowing liquid to run out of it
dream - a state of mind characterized by abstraction and release from reality; a series of mental images and emotions occurring during sleep; imaginative thoughts indulged in while awake; someone or something wonderful; a fantastic but vain hope (from fantasies induced by the opium pipe); a cherished desire; verb have a daydream; indulge in a fantasy; experience while sleeping
drinking water - water suitable for drinking
dronabinol - psychoactive substance present in marijuana; used therapeutically to control nausea associated with cancer therapy
drool - saliva spilling from the mouth; pretentious or silly talk or writing; verb let saliva drivel from the mouth; be envious, desirous, eager for, or extremely happy about something
drowsiness - a very sleepy state
drug abuse - excessive use of drugs
dry ice - solidified carbon dioxide; dry ice sublimates at -78.5 C and is used mainly as a refrigerant
duct - an enclosed conduit for a fluid; a bodily passage or tube lined with epithelial cells and conveying a secretion or other substance; a continuous tube formed by a row of elongated cells lacking intervening end walls
duodenal ulcer - a peptic ulcer of the duodenum
duodenum - the part of the small intestine between the stomach and the jejunum
dura mater - the outermost (and toughest) of the 3 meninges
dust - fine powdery material such as dry earth or pollen that can be blown about in the air; free microscopic particles of solid material; the remains of something that has been destroyed or broken up; verb remove the dust from; rub the dust over a surface so as to blur the outlines of a shape; cover with a light dusting of a substance; distribute loosely
dwarfism - a genetic abnormality resulting in short stature
dye - a usually soluble substance for staining or coloring e.g. fabrics or hair; verb color with dye
dysarthria - impaired articulatory ability resulting from defects in the peripheral motor nerves or in the speech musculature
dyscalculia - impaired ability to learn grade-appropriate mathematics
dysgraphia - impaired ability to learn to write
dyskinesia - abnormality in performing voluntary muscle movements
dyslexia - impaired ability to learn to read
dysmenorrhea - painful menstruation
dyspepsia - a disorder of digestive function characterized by discomfort or heartburn or nausea
dysphagia - condition in which swallowing is difficult or painful
dysphasia - an impairment of language (especially speech production) that is usually due to brain damage
dysphonia - speech disorder attributable to a disorder of phonation
dysplasia - abnormal development (of organs or cells) or an abnormal structure resulting from such growth
dyspnea - difficult or labored respiration
dysuria - painful or difficult urination
ear canal - either of the passages in the outer ear from the auricle to the tympanic membrane
ear - the sense organ for hearing and equilibrium; good hearing; attention to what is said; fruiting spike of a cereal plant especially corn; the externally visible cartilaginous structure of the external ear
earache - an ache localized in the middle or inner ear
eat - verb eat a meal; take a meal; take in solid food; worry or cause anxiety in a persistent way; cause to deteriorate due to the action of water, air, or an acid; use up (resources or materials); take in food; used of animals only
eating disorder - a disorder of the normal eating routine
ecchymosis - the escape of blood from ruptured blood vessels into the surrounding tissue to form a purple or black-and-blue spot on the skin; the purple or black-and-blue area resulting from a bruise
eccrine gland - a small sweat gland the produces only a fluid; restricted to the human skin
echinacea - small genus of North American coarse perennial herbs
echinococcosis - infestation with larval echinococci (tapeworms)
echinodermata - radially symmetrical marine invertebrates including e.g. starfish and sea urchins and sea cucumbers
echocardiograph - a sonograph that creates an image of the heart and its abnormalities
echocardiography - a noninvasive diagnostic procedure that uses ultrasound to study to structure and motions of the heart
echolalia - (psychiatry) mechanical and meaningless repetition of the words of another person (as in schizophrenia); an infant's repetition of sounds uttered by others
echolocation - determining the location of something by measuring the time it takes for an echo to return from it
echovirus - any of a group of viruses associated with various diseases including viral meningitis and mild respiratory disorders and diarrhea in newborn infants
eclampsia - a toxic condition characterized by convulsions and possibly coma during or immediately after pregnancy
ecology - the branch of biology concerned with the relations between organisms and their environment; the environment as it relates to living organisms
ectoderm - the outer germ layer that develops into skin and nervous tissue
ectopic pregnancy - pregnancy resulting from gestation elsewhere than in the uterus
eczema - generic term for inflammatory conditions of the skin; particularly with vesiculation in the acute stages
edema - swelling from excessive accumulation of serous fluid in tissue
efferent nerve - a nerve that conveys impulses toward or to muscles or glands
effusion - flow under pressure; an unrestrained expression of emotion
eicosapentaenoic acid - an omega-3 fatty acid with 20 carbon atoms; found in fish (especially tuna and bluefish)
ejaculation - an abrupt emphatic exclamation expressing emotion; the discharge of semen in males
elastic tissue - connective tissue consisting chiefly of elastic fibers found in the dermis of the skin and in the walls of veins and arteries and in some tendons and ligaments
elastin - a fibrous scleroprotein found in elastic tissues such as the walls of arteries
elastomer - any of various elastic materials that resemble rubber (resumes its original shape when a deforming force is removed)
elastosis - breakdown of elastic tissue (as the loss of elasticity in the skin of elderly people that results from degeneration of connective tissue)
elbow joint - hinge joint between the forearm and upper arm and the corresponding joint in the forelimb of a quadruped
elbow - the joint of a mammal or bird that corresponds to the human elbow; the part of a sleeve that covers the elbow joint; a sharp bend in a road or river; a length of pipe with a sharp bend in it; hinge joint between the forearm and upper arm and the corresponding joint in the forelimb of a quadruped; verb shove one's elbow into another person's ribs; push one's way with the elbows
electric organ - (music) an electronic simulation of a pipe organ
electrocardiography - diagnostic procedure consisting of recording the activity of the heart electronically with a cardiograph (and producing a cardiogram)
electroconvulsive therapy - the administration of a strong electric current that passes through the brain to induce convulsions and coma
electrode - a conductor used to make electrical contact with some part of a circuit
electrolysis - removing superfluous or unwanted hair by passing an electric current through the hair root; (chemistry) a chemical decomposition reaction produced by passing an electric current through a solution containing ions
electrolyte - a solution that conducts electricity
electromyograph - a medical instrument that records the electrical waves associated with the activity of skeletal muscles
electromyography - diagnosis of neuromuscular disorders with the use of an electromyograph
electron microscopy - microscopy with the use of electron microscopes
electron - an elementary particle with negative charge
electrophoresis - the motion of charged particles in a colloid under the influence of an electric field; particles with a positive charge go to the cathode and negative to the anode
elephantiasis - hypertrophy of certain body parts (usually legs and scrotum); the end state of the disease filariasis
eligible - qualified for or allowed or worthy of being chosen
elixir - a substance believed to cure all ills; a sweet flavored liquid (usually containing a small amount of alcohol) used in compounding medicines to be taken by mouth in order to mask an unpleasant taste; a hypothetical substance that the alchemists believed to be capable of changing base metals into gold
emaciation - extreme leanness (usually caused by starvation or disease)
embolectomy - surgical removal of an embolus (usually from an artery)
embolism - occlusion of a blood vessel by an embolus (a loose clot or air bubble or other particle); an insertion into a calendar
embolus - an abnormal particle (e.g. an air bubble or part of a clot) circulating in the blood
embryo - an animal organism in the early stages of growth and differentiation that in higher forms merge into fetal stages but in lower forms terminate in commencement of larval life; (botany) a minute rudimentary plant contained within a seed or an archegonium
embryology - the branch of biology that studies the formation and early development of living organisms
embryonal carcinoma - malignant neoplasm of the testis
embryonal rhabdomyosarcoma - form of rhabdomyosarcoma occurring mainly in infants and children
embryonic cell - a cell of an embryo
emetic - a medicine that induces nausea and vomiting
emotion - any strong feeling
empathy - understanding and entering into another's feelings
employee - a worker who is hired to perform a job
empyema - a collection of pus in a body cavity (especially in the lung cavity)
emulsion - a light-sensitive coating on paper or film; consists of fine grains of silver bromide suspended in a gelatin; (chemistry) a colloid in which both phases are liquids
enalapril - an ACE inhibitor (trade name Vasotec) that blocks the formation of angiotensin in the kidney and so results in vasodilation; administered after heart attacks
enanthema - eruption on a mucous membrane (as the inside of the mouth) occurring as a symptom of a disease
encephalitis - inflammation of the brain usually caused by a virus; symptoms include headache and neck pain and drowsiness and nausea and fever (`phrenitis' is no longer in scientific use)
encephalomyelitis - inflammation of the brain and spinal cord
encephalopathy - any disorder or disease of the brain
enchondroma - benign slow-growing tumor of cartilaginous cells at the ends of tubular bones (especially in the hands and feet)
encopresis - involuntary defecation not attributable to physical defects or illness
endarterectomy - surgical removal of the inner lining of an artery that is clogged with atherosclerosis
endarteritis - inflammation of the inner lining of an artery
endocarditis - inflammation of the endocardium and heart valves
endocardium - the membrane that lines the cavities of the heart and forms part of the heart valves
endocrine gland - any of the glands of the endocrine system that secrete hormones directly into the bloodstream
endocrine system - the system of glands that produce endocrine secretions that help to control bodily metabolic activity
endocrine - of or belonging to endocrine glands or their secretions; any of the glands of the endocrine system that secrete hormones directly into the bloodstream; the secretion of an endocrine gland that is transmitted by the blood to the tissue on which it has a specific effect
endocrinology - the branch of medicine dealing with the endocrine glands and their secretions
endoderm - the inner germ layer that develops into the lining of the digestive and respiratory systems
endodontics - the branch of dentistry dealing with diseases of the dental pulp
endodontist - a dentist specializing in diseases of the dental pulp and nerve
endolymph - the bodily fluid that fills the membranous labyrinth of the inner ear
endometrial carcinoma - cancer of the uterine lining
endometrial - of or relating to the endometrium
endometriosis - the presence of endometrium elsewhere than in the lining of the uterus; causes premenstrual pain and dysmenorrhea
endometritis - inflammation of the lining of the uterus (of the endometrium)
endometrium - (pregnancy) the mucous membrane that lines the uterus; thickens under hormonal control and (if pregnancy does not occur) is shed in menstruation; if pregnancy occurs it is shed along with the placenta at parturition
endorphin - a neurochemical occurring naturally in the brain and having analgesic properties
endoscope - a long slender medical instrument for examining the interior of a bodily organ or performing minor surgery
endoscopy - visual examination of the interior of a hollow body organ by use of an endoscope
endothelium - an epithelium of mesoblastic origin; a thin layer of flattened cells that lines the inside of some body cavities
endotoxin - a toxin that is confined inside the microorganisms and is released only when the microorganisms are broken down or die
enema - injection of a liquid through the anus to stimulate evacuation; sometimes used for diagnostic purposes
enflurane - a nonflammable liquid (trade name Ethrane) used as an inhalation general anesthetic
enkephalin - an endorphin having opiate qualities that occurs in the brain and spinal cord and elsewhere
enteric bacteria - rod-shaped Gram-negative bacteria; most occur normally or pathogenically in intestines of humans and other animals
enteritis - inflammation of the intestine (especially the small intestine); usually characterized by diarrhea
enterobacteriaceae - a large family of Gram-negative rod-shaped bacteria of the order Eubacteriales
enterobiasis - an infestation with or a resulting infection caused by the pinworm Enterobius vermicularis; occurs especially in children
enterobius - pinworms
enterotoxin - a cytotoxin specific for the cells of the intestinal mucosa
enterovirus - any of a group of picornaviruses that infect the gastrointestinal tract and can spread to other areas (especially the nervous system)
enuresis - inability to control the flow of urine and involuntary urination
environment - the area in which something exists or lives; the totality of surrounding conditions
enzyme - any of several complex proteins that are produced by cells and act as catalysts in specific biochemical reactions
eosinophil - a leukocyte readily stained with eosin
eosinophilia - a symptom of allergic states; increased eosinophils in the blood
ependyma - thin epithelial membrane lining the ventricles of the brain and the spinal cord canal
ephedrine - white odorless powdered or crystalline alkaloid from plants of the genus Ephedra (especially Ephedra sinica) or made synthetically; used as a bronchodilator to treat bronchitis and asthma
epicardium - the innermost of the two layers of the pericardium
epicondylitis - painful inflammation of the muscles and soft tissues around an epicondyle
epidemiologist - a medical scientist who studies the transmission and control of epidemic diseases
epidemiology - the branch of medical science dealing with the transmission and control of disease
epidermis - the outer layer of the skin covering the exterior body surface of vertebrates
epididymis - a convoluted tubule in each testis; carries sperm to vas deferens
epididymitis - painful inflammation of the epididymis
epidural anesthesia - regional anesthesia resulting from injection of an anesthetic into the epidural space of the spinal cord; sensation is lost in the abdominal and genital and pelvic areas; used in childbirth and gynecological surgery
epigastric artery - one of three arteries supplying the anterior walls of the abdomen
epigastric - lying on or over the stomach; of or relating to the anterior walls of the abdomen
epigastrium - the region lying on or over the stomach (just below the sternum)
epiglottis - a flap of cartilage that covers the windpipe while swallowing
epiglottitis - inflammation of the epiglottis; characterized by fever and a severe sore throat and difficulty in swallowing
epilepsy - a disorder of the central nervous system characterized by loss of consciousness and convulsions
epinephrine - a catecholamine secreted by the adrenal medulla in response to stress (trade name Adrenalin); stimulates autonomic nerve action
epiphysis - the end of a long bone; initially separated from the main bone by a layer of cartilage that eventually ossifies so the parts become fused; a small endocrine gland in the brain; situated beneath the back part of the corpus callosum; secretes melatonin
episcleritis - inflammation of the sclera of the eye
episiotomy - surgical incision of the perineum to enlarge the vagina and so facilitate delivery during childbirth
epispadias - a congenital abnormality in males in which the urethra is on the upper surface of the penis
epistaxis - bleeding from the nose
epithelial - of or belonging to the epithelium
epithelioma - a malignant tumor of the epithelial tissue
epithelium - membranous tissue covering internal organs and other internal surfaces of the body
epitope - the site on the surface of an antigen molecule to which an antibody attaches itself
erbium - a trivalent metallic element of the rare earth group; occurs with yttrium
ergocalciferol - a fat-soluble vitamin that prevents rickets
ergonomics - the branch of engineering science in which biological science is used to study the relation between workers and their environments
ergosterol - a plant sterol that is converted into vitamin D by ultraviolet radiation
ergotamine - an alkaloid derived from ergot that is less toxic than ergot; causes constriction of blood vessels and is used to treat migraine
eructation - a reflex that expels wind noisily from the stomach through the mouth; (of volcanos) pouring out fumes of lava (or a deposit so formed)
erysipelas - an acute streptococcal infection characterized by deep-red inflammation of the skin and mucous membranes
erythema multiforme - a red rash caused by hypersensitivity to a drug or disease or other allergen
erythema nodosum - skin condition characterized by tender red nodules on the shins and legs
erythema - abnormal redness of the skin resulting from dilation of blood vessels (as in sunburn or inflammation)
erythroblast - a nucleated cell in bone marrow from which red blood cells develop
erythroblastosis fetalis - severe anemia in newborn babies; the result of Rh incompatibility between maternal and fetal blood; typically occurs when the child of an Rh-negative mother inherits Rh-positive blood from the father; can be diagnosed before birth by amniocentesis
erythrocyte - a mature blood cell that contains hemoglobin to carry oxygen to the bodily tissues; a biconcave disc that has no nucleus
erythromycin - an antibiotic (trade name Erythrocin or E-Mycin or Ethril or Ilosone or Pediamycin) obtained from the actinomycete Streptomyces erythreus; effective against many Gram-positive bacteria and some Gram-negative
erythropoiesis - the process of producing red blood cells by the stem cells in the bone marrow
erythropoietin - a glycoprotein secreted by the kidneys that stimulates the production of red blood cells
escherichia coli - a species of bacterium normally present in intestinal tract of humans and other animals; sometimes pathogenic; can be a threat to food safety
escherichia - a genus of enteric bacteria
esophageal - relating to the esophagus
esophagitis - inflammation of the esophagus; often caused by gastroesophageal reflux
esophagogastric junction - the junction between the esophagus and the stomach epithelium
esophagoscope - an optical instrument for examining the inside of the esophagus
esophagus - the passage between the pharynx and the stomach
esotropia - strabismus in which one or both eyes turn inward toward the nose
essential hypertension - persistent and pathological high blood pressure for which no specific cause can be found
estazolam - a frequently prescribed sleeping pill (trade name ProSom)
ester - formed by reaction between an acid and an alcohol with elimination of water
esthesia - mental responsiveness and awareness
estivation - (botany) the arrangement of sepals and petals in a flower bud before it opens; (zoology) cessation or slowing of activity during the summer; especially slowing of metabolism in some animals during a hot or dry period
estradiol - the most powerful female hormone that occurs naturally; synthesized and used to treat estrogen deficiency and breast cancer
estriol - a naturally occurring estrogenic hormone; a synthetic form is used to treat estrogen deficiency
estrogen - a general term for female steroid sex hormones that are secreted by the ovary and responsible for typical female sexual characteristics
estrone - a naturally occurring weak estrogenic hormone secreted by the mammalian ovary; synthesized (trade name Estronol) and used to treat estrogen deficiency
estrus - applies to nonhuman mammals: a state or period of heightened sexual arousal and activity
etanercept - a genetically engineered anti-TNF compound (trade name Enbrel) consisting of receptors that bind TNF; it is injected twice a week in the treatment of rheumatoid arthritis
ethacrynic acid - diuretic (trade name Edecrin) used to treat edema
ethane - a colorless odorless alkane gas used as fuel
ethanol - the intoxicating agent in fermented and distilled liquors; used pure or denatured as a solvent or in medicines and colognes and cleaning solutions and rocket fuel; proposed as a renewable clean-burning additive to gasoline
ethchlorvynol - a mild sedative-hypnotic drug (trade name Placidyl)
ether - a colorless volatile highly inflammable liquid formerly used as an inhalation anesthetic; a medium that was once supposed to fill all space and to support the propagation of electromagnetic waves; any of a class of organic compounds that have two hydrocarbon groups linked by an oxygen atom; the fifth and highest element after air and earth and fire and water; was believed to be the substance composing all heavenly bodies
ethics - the philosophical study of moral values and rules; motivation based on ideas of right and wrong
ethmoid sinus - a sinus of the meatuses of the nasal cavity (behind the bridge of the nose)
ethosuximide - an anticonvulsant drug (trade names Emeside and Zarontin) used to treat petit mal epilepsy
ethylene glycol - a sweet but poisonous syrupy liquid used as an antifreeze and solvent
ethylene - a flammable colorless gaseous alkene; obtained from petroleum and natural gas and used in manufacturing many other chemicals; sometimes used as an anesthetic
etiology - the philosophical study of causation; the cause of a disease
etodolac - a nonsteroidal anti-inflammatory drug (trade name Lodine)
eubacterium - a large group of bacteria having rigid cell walls; motile types have flagella
euglena - minute single-celled green freshwater organism having a single flagella; often classed as algae
eukaryote - an organism with cells characteristic of all life forms except primitive microorganisms such as bacteria; i.e. an organism with `good' or membrane-bound nuclei in its cells
euphoria - a feeling of great (usually exaggerated) elation
europium - a bivalent and trivalent metallic element of the rare earth group
eurotium - a genus of fungi belonging to the order Eurotiales
eustachian tube - either of the paired tubes connecting the middle ears to the nasopharynx; equalizes air pressure on the two sides of the eardrum
evoked potential - the electrical response of the central nervous system produced by an external stimulus
evolution - (biology) the sequence of events involved in the evolutionary development of a species or taxonomic group of organisms; a process in which something passes by degrees to a different stage (especially a more advanced or mature stage)
exanthema - eruption on the skin occurring as a symptom of a disease
excretion - the bodily process of discharging waste matter; waste matter (as urine or sweat but especially feces) discharged from the body
exenteration - surgical removal of the organs within a body cavity (as those of the pelvis)
exercise - the activity of exerting your muscles in various ways to keep fit; a task performed or problem solved in order to develop skill or understanding; systematic training by multiple repetitions; (usually plural) a ceremony that involves processions and speeches; the act of using; verb do physical exercise; give a workout to; learn by repetition; put to use; carry out or practice; as of jobs and professions
exhibitionism - the perverse act of exposing and attracting attention to your own genitals; extravagant and conspicuous behavior intended to attract attention to yourself
exocrine gland - a gland that secretes externally through a duct
exon - sequence of a gene's DNA that transcribes into protein structures
exonuclease - a nuclease that releases one nucleotide at a time (serially) beginning at one of a nucleic acid
exophthalmos - protrusion of the eyeball from the socket
exostosis - a benign outgrowth from a bone (usually covered with cartilage)
exotropia - strabismus in which one or both eyes are directed outward
expectancy - something expected (as on the basis of a norm); pleasurable expectation
expectorant - a medicine promoting expectoration
experience - the accumulation of knowledge or skill that results from direct participation in events or activities; the content of direct observation or participation in an event; an event as apprehended; verb go through (mental or physical states or experiences); go or live through; undergo; have firsthand knowledge of states, situations, emotions, or sensations; undergo an emotional sensation
exposure - the act of subjecting someone to an influencing experience; abandoning without shelter or protection (as by leaving as infant out in the open); presentation to view in an open or public manner; the act of exposing film to light; vulnerability to the elements; to the action of heat or cold or wind or rain; aspect re light or wind; the disclosure of something secret; the intensity of light falling on a photographic film or plate; a picture of a person or scene in the form of a print or transparent slide; recorded by a camera on light-sensitive material; the state of being vulnerable or exposed
extent - the distance or area or volume over which something extends; the point or degree to which something extends
external ear - the part of the ear visible externally
extraction - the act of pulling out (as a tooth); the process of obtaining something from a mixture or compound by chemical or physical or mechanical means; properties attributable to your ancestry
extravasation - the process of exuding or passing out of a vessel into surrounding tissues; said of blood or lymph or urine; an extravasated liquid (blood or lymph or urine); the product of extravasation; (of volcanos) pouring out fumes of lava (or a deposit so formed)
exudate - a substance that oozes out from plant pores; verb release (a liquid) in drops or small quantities
eye infection - an infection of the sebaceous gland of the eyelid
eye movement - the movement of the eyes
eye - a small hole or loop (as in a needle); the organ of sight; good discernment (either visually or as if visually); attention to what is seen; an area that is approximately central within some larger region; verb look at
eyeglass - lens for correcting defective vision in one eye; held in place by facial muscles
eyelash - any of the short curved hairs that grow from the edges of the eyelids
eyelid - either of two folds of skin that can be moved to cover or open the eye
facial expression - a gesture executed with the facial muscles; the feelings expressed on a person's face
facial muscle - any of the skeletal muscles of the face
facial nerve - cranial nerve that supplies facial muscles
factor v - a coagulation factor
factor vii - a coagulation factor formed in the kidney under the influence of vitamin K
factor viii - a coagulation factor (trade name Hemofil) whose absence is associated with hemophilia A
factor xii - coagulation factor whose deficiency results in prolongation of clotting time of venous blood
factor xiii - in the clotting of blood thrombin catalyzes factor XIII into its active form (fibrinase) which causes fibrin to form a stable clot
faculty - one of the inherent cognitive or perceptual powers of the mind; the body of teachers and administrators at a school
falciform ligament - a ligament that attaches part of the liver to the diaphragm and the abdominal wall
fall - a lapse into sin; a loss of innocence or of chastity; a movement downward; a sudden decline in strength or number or importance; when a wrestler's shoulders are forced to the mat; the lapse of mankind into sinfulness because of the sin of Adam and Eve; the season when the leaves fall from the trees; the act of surrendering (under agreed conditions); a sudden drop from an upright position; a sudden sharp decrease in some quantity; a free and rapid descent by the force of gravity; a downward slope or bend; the time of day immediately following sunset; verb pass suddenly and passively into a state of body or mind; come as if by falling; go as if by falling; occur at a specified time or place; begin vigorously; be born, used chiefly of lambs; come out; issue; be cast down; assume a disappointed or sad expression; descend in free fall under the influence of gravity; drop oneself to a lower or less erect position; lose an upright position suddenly; slope downward; move in a specified direction; be inherited by; fall to somebody by assignment or lot; be captured; to be given by assignment or distribution; to be given by right or inheritance; lose office or power; suffer defeat, failure, or ruin; yield to temptation or sin; lose one's chastity; touch or seem as if touching visually or audibly; die, as in battle or in a hunt; be due; come under, be classified or included; decrease in size, extent, or range; fall or flow in a certain way; move downward and lower, but not necessarily all the way; come into the possession of; fall from clouds
fallopian tube - either of a pair of tubes conducting the egg from the ovary to the uterus
family medicine - medical practice that provides health care regardless of age or sex while placing emphasis on the family unit
family planning - limiting the number of children born
family therapy - any of several therapeutic approaches in which a family is treated as a whole
famotidine - a histamine blocker (trade name Pepcid) used to treat peptic ulcers and gastritis and esophageal reflux
farad - the capacitance of a capacitor that has an equal and opposite charge of 1 coulomb on each plate and a voltage difference of 1 volt between the plates
farmer's lung - alveolitis caused by an allergic reaction to fungal spores in the dust that is inhaled from moldy hay
fascia - a sheet or band of fibrous connective tissue separating or binding together muscles and organs etc
fasciculation - muscular twitching of contiguous groups of muscle fibers
fasciola hepatica - flatworm parasitic in liver and bile ducts of domestic animals and humans
fasciola - a genus of Fasciolidae
fascioliasis - infestation with the liver fluke Fasciola hepatica; liver damage sometimes occurs; related to liver rot
fasciolopsis buski - fluke that is parasitic on humans and swine; common in eastern Asia
fasting - abstaining from food
fatigue - (always used with a modifier) boredom resulting from overexposure to something; temporary loss of strength and energy resulting from hard physical or mental work; used of materials (especially metals) in a weakened state caused by long stress; labor of a nonmilitary kind done by soldiers (cleaning or digging or draining or so on); verb exhaust or get tired through overuse or great strain or stress; get tired of something or somebody
fatty acid - any of a class of aliphatic monocarboxylic acids that form part of a lipid molecule and can be derived from fat by hydrolysis; fatty acids are simple molecules built around a series of carbon atoms linked together in a chain of 12 to 22 carbon atoms
fatty liver - yellow discoloration as a result of the accumulation of certain fats (triglycerides) in the liver; can be caused by alcoholic cirrhosis or pregnancy or exposure to certain toxins
favism - anemia resulting from eating fava beans; victims have an inherited blood abnormality and enzyme deficiency
fear - an emotion experienced in anticipation of some specific pain or danger (usually accompanied by a desire to flee or fight); a profound emotion inspired by a deity; an anxious feeling; verb be afraid or scared of; be frightened of; be uneasy or apprehensive about; be sorry; used to introduce an unpleasant statement; be afraid or feel anxious or apprehensive about a possible or probable situation or event; regard with feelings of respect and reverence; consider hallowed or exalted or be in awe of
fecal impaction - accumulation of hardened feces in the rectum or lower colon which the person cannot move
feces - solid excretory product evacuated from the bowels
female genitalia - external female sex organs
female - being the sex (of plant or animal) that produces fertilizable gametes (ova) from which offspring develop; for or pertaining to or composed of women or girls; characteristic of or peculiar to a woman; an animal that produces gametes (ova) that can be fertilized by male gametes (spermatozoa); a person who belongs to the sex that can have babies
feminization - the process of becoming feminized; the development of female characteristics (loss of facial hair or breast enlargement) in a male because of hormonal disorders or castration
femoral artery - the chief artery of the thigh; a continuation of the external iliac artery
femoral vein - a vein that accompanies the femoral artery in the same sheath; a continuation of the popliteal vein; becomes the external iliac vein
femur - the longest and thickest bone of the human skeleton; extends from the pelvis to the knee
fenoprofen - a nonsteroidal anti-inflammatory drug (trade name Nalfon) used in the treatment of arthritis and other painful inflammatory disorders
fentanyl - trade names of a narcotic analgesic that can be inhaled and that acts on the central nervous system and may become addictive; used as a veterinary anesthetic and with other drugs before, during, and after surgery; also used as a nonlethal gas to incapacitate people in hostage situations; also abused as a recreational drug
fermentation - a process in which an agent causes an organic substance to break down into simpler substances; especially, the anaerobic breakdown of sugar into alcohol; a state of agitation or turbulent change or development
ferritin - a protein containing 20% iron that is found in the intestines and liver and spleen; it is one of the chief forms in which iron is stored in the body
fertility - the state of being fertile; capable of producing offspring; the property of producing abundantly and sustaining vigorous and luxuriant growth; the ratio of live births in an area to the population of that area; expressed per 1000 population per year
fertilization - making fertile as by applying fertilizer or manure; creation by the physical union of male and female gametes; of sperm and ova in an animal or pollen and ovule in a plant
fetal alcohol syndrome - a medical condition in which body deformation or facial development or mental ability of a fetus is impaired because the mother drank alcohol while pregnant
fetal distress - an abnormal condition of a fetus; usually discovered during pregnancy and characterized by an abnormal heart rhythm
fetus - an unborn or unhatched vertebrate in the later stages of development showing the main recognizable features of the mature animal
fever - intense nervous anticipation; a rise in the temperature of the body; frequently a symptom of infection
fiber - a leatherlike material made by compressing layers of paper or cloth; a slender and greatly elongated solid substance; the inherent complex of attributes that determine a persons moral and ethical actions and reactions
fibrin - a white insoluble fibrous protein formed by the action of thrombin on fibrinogen when blood clots; it forms a network that traps red cells and platelets
fibrinogen - a protein present in blood plasma; converts to fibrin when blood clots
fibrinolysis - a normal ongoing process that dissolves fibrin and results in the removal of small blood clots
fibroadenoma - benign and movable and firm and not tender tumor of the breast; common in young women and caused by high levels of estrogen
fibroblast - a cell from which connective tissue develops
fibrocartilage - cartilage that is largely composed of fibers like those in ordinary connective tissue
fibroid tumor - benign tumor containing fibrous tissue (especially in the uterus)
fibroma - nonmalignant tumor of connective tissue
fibrosis - development of excess fibrous connective tissue in an organ
fibula - the outer and thinner of the two bones of the human leg between the knee and ankle
filariasis - a disease caused by nematodes in the blood or tissues of the body causing blockage of lymphatic vessels
filoviridae - a family of threadlike RNA viruses that cause diseases in humans and nonhuman primates (monkeys and chimpanzees)
finger - one of the parts of a glove that provides covering for a finger or thumb; any of the terminal members of the hand (sometimes excepting the thumb); the length of breadth of a finger used as a linear measure; verb indicate the fingering for the playing of musical scores for keyboard instruments; feel or handle with the fingers; search for on the computer; examine by touch
first aid - emergency care given before regular medical aid can be obtained
fish oil - a fatty oil obtained from the livers of various fish
fistula - an abnormal passage leading from a suppurating cavity to the body surface; a chronic inflammation of the withers of a horse
fixative - a varnish dissolved in alcohol and sprayed over pictures to prevent smudging; a compound (such as ethanol or formaldehyde) that fixes tissues and cells for microscopic study
flagellum - a lash-like appendage used for locomotion (e.g., in sperm cells and some bacteria and protozoa); a whip used to inflict punishment (often used for pedantic humor)
flatfoot - a foot afflicted with a fallen arch; abnormally flattened and spread out; a policeman who patrols a given region
flatulence - a state of excessive gas in the alimentary canal; pompously embellished language
flavin - a ketone that forms the nucleus of certain natural yellow pigments like riboflavin
flaviviridae - a family of arboviruses carried by arthropods
flavivirus - animal viruses belonging to the family Flaviviridae
flea - any wingless bloodsucking parasitic insect noted for ability to leap
flecainide - oral antiarrhythmic medication (trade name Tambocor) used as a last resort in treating arrhythmias; increases the risk of sudden death in heart attack patients
flocculation - the process of flocculating; forming woolly cloudlike aggregations
floxuridine - antineoplastic drug used to treat some cancers; can cause loss of hair
fluorescein - a yellow dye that is visible even when highly diluted; used as an absorption indicator when silver nitrate solution is added to sodium chloride in order to precipitate silver chloride (turns pink when no chloride ions are left in solution and negative fluorescein ions are then absorbed)
fluorescence microscopy - light microscopy in which the specimen is irradiated at wavelengths that excite fluorochromes
fluorescent dye - a yellow dye that is visible even when highly diluted; used as an absorption indicator when silver nitrate solution is added to sodium chloride in order to precipitate silver chloride (turns pink when no chloride ions are left in solution and negative fluorescein ions are then absorbed)
fluoride - a salt of hydrofluoric acid
fluorine - a nonmetallic univalent element belonging to the halogens; usually a yellow irritating toxic flammable gas; a powerful oxidizing agent; recovered from fluorite or cryolite or fluorapatite
fluoroscopy - examination of body structures using a fluoroscope
fluorouracil - an antimetabolite used to treat certain cancers
fluoxetine - a selective-serotonin reuptake inhibitor commonly prescribed as an antidepressant (trade name Prozac)
fluphenazine - tranquilizer used to treat psychotic disorders
flurazepam - tranquilizer (trade name Dalmane) used to treat insomnia
flurbiprofen - a nonsteroidal anti-inflammatory drug (trade name Ansaid) that is administered only orally
fmri - a form of magnetic resonance imaging of the brain that registers blood flow to functioning areas of the brain
focal seizure - transitory disturbance in motor or sensory function resulting from abnormal cortical activity
focal - having or localized centrally at a focus; of or relating to a focus
folate - a B vitamin that is essential for cell growth and reproduction
folic acid - a B vitamin that is essential for cell growth and reproduction
follicle - any small spherical group of cells containing a cavity
folliculitis - inflammation of a hair follicle
food allergy - allergic reaction to a substance ingested in food
food poisoning - illness caused by poisonous or contaminated food
foot - travel by walking; any of various organs of locomotion or attachment in invertebrates; a support resembling a pedal extremity; the part of the leg of a human being below the ankle joint; the lower part of anything; a member of a surveillance team who works on foot or rides as a passenger; a linear unit of length equal to 12 inches or a third of a yard; the pedal extremity of vertebrates other than human beings; lowest support of a structure; (prosody) a group of 2 or 3 syllables forming the basic unit of poetic rhythm; an army unit consisting of soldiers who fight on foot; verb add a column of numbers; walk; pay for something
forceps - an extractor consisting of a pair of pincers used in medical treatment (especially for the delivery of babies)
forearm - the part of the superior limb between the elbow and the wrist; verb arm in advance of a confrontation
forehead - the large cranial bone forming the front part of the cranium: includes the upper part of the orbits; the part of the face above the eyes
forensic medicine - the branch of medical science that uses medical knowledge for legal purposes
foreskin - a fold of skin covering the tip of the penis; a fold of skin covering the tip of the clitoris
formaldehyde - a colorless poisonous gas; made by the oxidation of methanol
formication - hallucinated sensation that insects or snakes are crawling over the skin; a common side-effect of extensive use of cocaine or amphetamines
fourier analysis - analysis of a periodic function into a sum of simple sinusoidal components
francisella tularensis - the type species of the genus Francisella and the causal agent of tularemia in humans; can be used as a bioweapon
francisella - a genus of Gram-negative aerobic bacteria that occur as pathogens and parasite in many animals (including humans)
free radical - an atom or group of atoms with at least one unpaired electron; in the body it is usually an oxygen molecule than has lost an electron and will stabilize itself by stealing an electron from a nearby molecule
freeze-drying - a method of drying food or blood plasma or pharmaceuticals or tissue without destroying their physical structure; material is frozen and then warmed in a vacuum so that the ice sublimes
friedreich's ataxia - sclerosis of the posterior and lateral columns of the spinal cord; characterized by muscular weakness and abnormal gait; occurs in children
frontal lobe - that part of the cerebral cortex in either hemisphere of the brain lying directly behind the forehead
frontal sinus - one of a pair of cavities in the frontal bone
frostbite - destruction of tissue by freezing and characterized by tingling, blistering and possibly gangrene
fructose - a simple sugar found in honey and in many ripe fruits
frustration - an act of hindering someone's plans or efforts; a feeling of annoyance at being hindered or criticized; the feeling that accompanies an experience of being thwarted in attaining your goals
fullerene - a form of carbon having a large molecule consisting of an empty cage of sixty or more carbon atoms
funding - the act of financing; financial resources provided to make some project possible
fundus - (anatomy) the base of a hollow organ or that part of the organ farthest from its opening
fungi - (pun) the one who buys the drinks; the taxonomic kingdom of lower plants
furan - a colorless toxic flammable liquid used in the synthesis of nylon
furosemide - commonly used diuretic (trade name Lasix) used to treat hypertension and edema
furunculosis - acute skin disease characterized by the presence of many furuncles
gadolinium - a ductile silvery-white ductile ferromagnetic trivalent metallic element of the rare earth group
gain - the amount by which the revenue of a business exceeds its cost of operating; the amount of increase in signal power or voltage or current expressed as the ratio of output to input; the advantageous quality of being beneficial; a quantity that is added; verb increase (one's body weight); increase in; obtain advantages, such as points, etc.; earn on some commercial or business transaction; earn as salary or wages; rise in rate or price; reach a destination, either real or abstract; win something through one's efforts; derive a benefit from; obtain
gait - a person's manner of walking; a horse's manner of moving; the rate of moving (especially walking or running)
galactose - a simple sugar found in lactose
galactosemia - a genetic disease (autosomal recessive) in which an enzyme needed to metabolize galactose is deficient or absent; typically develops shortly after birth
gallbladder - a muscular sac attached to the liver that secretes bile and stores it until needed for digestion
gallic acid - a colorless crystalline acid obtained from tannin
gallium - a rare silvery (usually trivalent) metallic element; brittle at low temperatures but liquid above room temperature; occurs in trace amounts in bauxite and zinc ores
gametogenesis - the development and maturation of sex cells through meiosis
gamma globulin - a plasma protein containing the immunoglobulins that are responsible for immune responses
gangrene - necrotic tissue; a mortified or gangrenous part or mass; the localized death of living cells (as from infection or the interruption of blood supply); verb undergo necrosis
garlic - aromatic bulb used as seasoning; bulbous herb of southern Europe widely naturalized; bulb breaks up into separate strong-flavored cloves
gas - the state of matter distinguished from the solid and liquid states by: relatively low density and viscosity; relatively great expansion and contraction with changes in pressure and temperature; the ability to diffuse readily; and the spontaneous tendency to become distributed uniformly throughout any container; a fluid in the gaseous state having neither independent shape nor volume and being able to expand indefinitely; a pedal that controls the throttle valve; a state of excessive gas in the alimentary canal; a volatile flammable mixture of hydrocarbons (hexane and heptane and octane etc.) derived from petroleum; used mainly as a fuel in internal-combustion engines; a fossil fuel in the gaseous state; used for cooking and heating homes; verb attack with gas; subject to gas fumes; show off
gastrectomy - surgical removal of all or part of the stomach
gastric juice - digestive secretions of the stomach glands consisting chiefly of hydrochloric acid and mucin and the enzymes pepsin and rennin and lipase
gastric ulcer - a peptic ulcer of the stomach
gastritis - inflammation of the lining of the stomach; nausea and loss of appetite and discomfort after eating
gastrocnemius muscle - the muscle in the back part of the leg that forms the greater part of the calf; responsible for the plantar flexion of the foot
gastroenteritis - inflammation of the stomach and intestines; can be caused by Salmonella enteritidis
gastroenterologist - a physician who specializes in diseases of the gastrointestinal tract
gastroesophageal reflux - reflux of stomach contents into the esophagus
gastrointestinal disorder - illness caused by poisonous or contaminated food
gastrointestinal system - the system that makes food absorbable into the body
gastrointestinal - of or relating to the stomach and intestines
gastroscope - a type of endoscope for visually examining the stomach
gastroscopy - visual examination of the stomach by means of a gastroscope inserted through the esophagus
gastrostomy - surgical creation of an opening through the abdominal wall into the stomach (as for gastrogavage)
gastrula - double-walled stage of the embryo resulting from invagination of the blastula; the outer layer of cells is the ectoderm and the inner layer differentiates into the mesoderm and endoderm
gastrulation - the process in which a gastrula develops from a blastula by the inward migration of cells
gaucher's disease - a rare chronic disorder of lipid metabolism of genetic origin
gauss - German mathematician who developed the theory of numbers and who applied mathematics to electricity and magnetism and astronomy and geodesy (1777-1855); a unit of magnetic flux density equal to 1 maxwell per square centimeter
gel - a colloid in a more solid form than a sol; a thin translucent membrane used over stage lights for color effects; verb become a gel; apply a styling gel to
gelatin - a thin translucent membrane used over stage lights for color effects; an edible jelly (sweet or pungent) made with gelatin and used as a dessert or salad base or a coating for foods; a colorless water-soluble glutinous protein obtained from animal tissues such as bone and skin
gemfibrozil - medication (trade name Lopid) used to lower the levels of triglyceride in the blood
gender - a grammatical category in inflected languages governing the agreement between s and pros and adjectives; in some languages it is quite arbitrary but in Indo-European languages it is usually based on sex or animateness; the properties that distinguish organisms on the basis of their reproductive roles
gene expression - conversion of the information encoded in a gene first into messenger RNA and then to a protein
gene mutation - a mutation due to an intramolecular reorganization of a gene
gene - (genetics) a segment of DNA that is involved in producing a polypeptide chain; it can include regions preceding and following the coding DNA as well as introns between the exons; it is considered a unit of heredity
general anesthesia - a state of total unconsciousness resulting from anesthetic drugs (as for a major surgical operation)
generalized seizure - a seizure (or a type of epilepsy characterized by such seizures) during which the patient becomes unconscious and has convulsions over the entire body
generalized - spread throughout a body or system; not biologically differentiated or adapted to a specific function or environment
generic drug - when the patent protection for a brand-name drug expires generic versions of the drug can be offered for sale if the FDA agrees
genetic counseling - guidance for prospective parents on the likelihood of genetic disorders in their future children
genetic disorder - a disease or disorder that is inherited genetically
genetic engineering - the technology of preparing recombinant DNA in vitro by cutting up DNA molecules and splicing together fragments from more than one organism
genetic marker - a specific gene that produces a recognizable trait and can be used in family or population studies
genetic screening - analyzing a group of people to determine genetic susceptibility to a particular disease
genetic - of or relating to the science of genetics; pertaining to or referring to origin; tending to occur among members of a family usually by heredity; of or relating to or produced by or being a gene
genetics - the branch of biology that studies heredity and variation in organisms
genital herpes - an infection caused by herpes simplex virus type 2 (HSV-2) that is usually transmitted by sexual contact; marked by recurrent attacks of painful eruptions on the skin and mucous membranes of the genital area
genital system - organs and tissues involved in the production and maturation of gametes and in their union and subsequent development as offspring
genitalia - external sex organ
genome - the ordering of genes in a haploid set of chromosomes of a particular organism; the full DNA sequence of an organism
genomics - the branch of genetics that studies organisms in terms of their genomes (their full DNA sequences)
genotype - the particular alleles at specified loci present in an organism; a group of organisms sharing a specific genetic constitution
gentamicin - an antibiotic (trade name Garamycin) that is derived from an actinomycete; used in treating infections of the urinary tract
gentian violet - a green crystal (violet in water) used as a dye or stain or bactericide or fungicide or anthelmintic or burn treatment
genu varum - a leg bowed outward at the knee (or below the knee)
geophagia - eating earth or clay or chalk; occurs in some primitive tribes or sometimes in cases of nutritional deficiency
geriatrician - a specialist in gerontology
geriatrics - the branch of medical science that deals with diseases and problems specific to old people
germ cell - a spermatozoon or an ovum
germ layer - (embryology) any of the 3 layers of cells differentiated in embryos following gastrulation
germ - a small apparently simple structure (as a fertilized egg) from which new tissue can develop into a complete organism; a minute life form (especially a disease-causing bacterium); the term is not in technical use; anything that provides inspiration for later work
germanium - a brittle grey crystalline element that is a semiconducting metalloid (resembling silicon) used in transistors; occurs in germanite and argyrodite
gestational age - the age of an embryo counting from the time of fertilization
ghrelin - a hormone produced by stomach cells
giardia - a suspected cause of diarrhea in humans
giardiasis - infection of the intestines with protozoa found in contaminated food and water; characterized by diarrhea and nausea and flatulence and abdominal discomfort
gigantism - excessive largeness of stature; excessive size; usually caused by excessive secretion of growth hormone from the pituitary gland
gill - respiratory organ of aquatic animals that breathe oxygen dissolved in water; any of the radiating leaflike spore-producing structures on the underside of the cap of a mushroom or similar fungus; a United States liquid unit equal to 4 fluid ounces; a British imperial capacity unit (liquid or dry) equal to 5 fluid ounces or 142.066 cubic centimeters
gingiva - the tissue (covered by mucous membrane) of the jaws that surrounds the bases of the teeth
gingivitis - inflammation of the gums
ginkgo biloba - deciduous dioecious Chinese tree having fan-shaped leaves and fleshy yellow seeds; exists almost exclusively in cultivation especially as an ornamental street tree
gland - any of various organs that synthesize substances needed by the body and release it through ducts or directly into the bloodstream
glanders - a destructive and contagious bacterial disease of horses that can be transmitted to humans
glans penis - the conical mass of erectile tissue that forms the head of the penis
glaucoma - increased pressure in the eyeball due to obstruction of the outflow of aqueous humor; damages the optic disc and impairs vision (sometimes progressing to blindness)
glioblastoma - a fast-growing malignant brain tumor composed of spongioblasts; nearly always fatal
glioma - a tumor of the brain consisting of neuroglia
globin - a colorless protein obtained by removing heme from hemoglobin; the oxygen carrying compound in red blood cells
globus pallidus - the inner pale yellow part of the lenticular nucleus
glomerulonephritis - nephritis marked by inflammation of the glomeruli of the kidney; characterized by decreased production of urine and by the presence of blood and protein in the urine and by edema
glossalgia - pain in the tongue
glossitis - inflammation of the tongue
glossopharyngeal nerve - sensory nerve to the pharynx and back of the tongue; motor fibers innervate muscles that elevate the pharynx and larynx; includes parasympathetic fibers to the otic ganglion
glossoptosis - abnormal downward or back placement of the tongue
glottis - the vocal apparatus of the larynx; the true vocal folds and the space between them where the voice tone is generated
glucagon - a hormone secreted by the pancreas; stimulates increases in blood sugar levels in the blood (thus opposing the action of insulin)
glucocorticoid - a steroid hormone that is produced by the adrenal cortex of animals; affects functioning of gonads and has anti-inflammatory activity
glucose - a monosaccharide sugar that has several forms; an important source of physiological energy
glutamate - a salt or ester of glutamic acid
glutamic acid - an amino acid occurring in proteins; important in the nitrogen metabolism of plants; used in monosodium glutamate to enhance the flavor of meats
glutamine - a crystalline amino acid occurring in proteins; important in protein metabolism
gluteal muscle - any one of three large skeletal muscles that form the buttock and move the thigh
glyburide - an oral antidiabetic drug (trade names DiaBeta and Micronase) that stimulates the release of insulin from the pancreas
glyceraldehyde - a sweet crystalline aldehyde formed by the breakdown of sugars
glyceride - an ester of glycerol and fatty acids that occurs naturally as fats and fatty oils
glycerol - a sweet syrupy trihydroxy alcohol obtained by saponification of fats and oils
glycine - genus of Asiatic erect or sprawling herbs: soya bean; the simplest amino acid found in proteins and the principal amino acid in sugar cane
glycogen - one form in which body fuel is stored; stored primarily in the liver and broken down into glucose when needed by the body
glycolysis - a metabolic process that breaks down carbohydrates and sugars through a series of reactions to either pyruvic acid or lactic acid and release energy for the body in the form of ATP
glycoprotein - a conjugated protein having a carbohydrate component
glycoside - a group of compounds derived from monosaccharides
glycosuria - the presence of abnormally high levels of sugar in the urine
goblet cell - an epithelial cell that secretes mucous
goiter - abnormally enlarged thyroid gland; can result from underproduction or overproduction of hormone or from a deficiency of iodine in the diet
gold - made from or covered with gold; having the deep slightly brownish color of gold; something likened to the metal in brightness or preciousness or superiority etc.; great wealth; coins made of gold; a soft yellow malleable ductile (trivalent and univalent) metallic element; occurs mainly as nuggets in rocks and alluvial deposits; does not react with most chemicals but is attacked by chlorine and aqua regia; a deep yellow color
golgi apparatus - a netlike structure in the cytoplasm of animal cells (especially in those cells that produce secretions)
gonad - a gland in which gametes (sex cells) are produced
gonadotropin - hormone secreted by the anterior pituitary gland and placenta; stimulates the gonads and controls reproductive activity
gonorrhea - a common venereal disease caused by the bacterium Neisseria gonorrhoeae; symptoms are painful urination and pain around the urethra
gout - a painful inflammation of the big toe and foot caused by defects in uric acid metabolism resulting in deposits of the acid and its salts in the blood and joints
government - the act of governing; exercising authority; (government) the system or form by which a community or other political unit is governed; the organization that is the governing authority of a political unit; the study of government of states and other political units
graafian follicle - a vascular body in a mammalian ovary enclosing a developing egg
gram - Danish physician and bacteriologist who developed a method of staining bacteria to distinguish among them (1853-1938); a metric unit of weight equal to one thousandth of a kilogram
gramicidin - an antibiotic produced by a soil bacterium; used chiefly as an antiseptic in treating local infections produced by Gram-positive bacteria
grandparent - a parent of your father or mother
granulation tissue - new connective tissue and tiny blood vessels that form on the surfaces of a wound during the healing process
granulocyte - a leukocyte that has granules in its cytoplasm
granuloma inguinale - a venereal disease caused by a bacterium of the genus Calymmatobacterium; characterized by a pimply rash of the skin in the genital and groin region
granuloma - a tumor composed of granulation tissue resulting from injury or inflammation or infection
gravidity - technical terms for pregnancy
gray matter - greyish nervous tissue containing cell bodies as well as fibers; forms the cerebral cortex consisting of unmyelinated neurons
grief - something that causes great unhappiness; intense sorrow caused by loss of a loved one (especially by death)
griseofulvin - a kind of penicillin (a fungicidal antibiotic with the trade name Fulvicin) produced by molds of the genus Penicillium
groin - the crease at the junction of the inner part of the thigh with the trunk together with the adjacent region and often including the external genitals; a protective structure of stone or concrete; extends from shore into the water to prevent a beach from washing away; verb build with groins
group therapy - psychotherapy in which a small group of individuals meet with a therapist; interactions among the members are considered to be therapeutic
growth factor - a protein that is involved in cell differentiation and growth
growth - vegetation that has grown; something grown or growing; (biology) the process of an individual organism growing organically; a purely biological unfolding of events involved in an organism changing gradually from a simple to a more complex level; a progression from simpler to more complex forms; (pathology) an abnormal proliferation of tissue (as in a tumor); the gradual beginning or coming forth; a process of becoming larger or longer or more numerous or more important
guanine - a purine base found in DNA and RNA; pairs with cytosine
guanosine - a nucleoside component of DNA; composed of guanine and deoxyribose
guarantor - one who provides a warrant or guarantee to another
guilt - remorse caused by feeling responsible for some offence; the state of having committed an offense
gynecologist - a specialist in gynecology
gynecology - the branch of medicine that deals with the diseases and hygiene of women
gynecomastia - excessive development of the breasts in males; usually the result of hormonal imbalance or treatment with certain drugs (including some antihypertensives)
habit - a pattern of behavior acquired through frequent repetition; a distinctive attire (as the costume of a religious order); an established custom; excessive use of drugs; verb put a habit on
hair follicle - a small tubular cavity containing the root of a hair; small muscles and sebaceous glands are associated with them
hair - a filamentous projection or process on an organism; any of the cylindrical filaments characteristically growing from the epidermis of a mammal; a covering for the body (or parts of it) consisting of a dense growth of threadlike structures (as on the human head); helps to prevent heat loss; filamentous hairlike growth on a plant; cloth woven from horsehair or camelhair; used for upholstery or stiffening in garments; a very small distance or space
hairy tongue - a benign side effect of some antibiotics; dark overgrowth of the papillae of the tongue
half-brother - a son of your stepparent by a former marriage
half-sister - a sister who has only one parent in common with you
halitosis - offensive breath
hallucination - an object perceived during a hallucinatory episode; illusory perception; a common symptom of severe mental disorder; a mistaken or unfounded opinion or idea
hallux - the first largest innermost toe
halogen - any of five related nonmetallic elements (fluorine or chlorine or bromine or iodine or astatine) that are all monovalent and readily form negative ions
haloperidol - tranquilizer (trade name Haldol) used to treat some psychotic disorders and Tourette's syndrome
halothane - a nonflammable inhalation anesthetic that produces general anesthesia; used along with analgesics and muscle relaxants for many types of surgical procedures
hamartoma - a focal growth that resembles a neoplasm but results from faulty development in an organ
hamate - the wrist bone in line with the 4th and 5th fingers
hand - physical assistance; terminal part of the forelimb in certain vertebrates (e.g. apes or kangaroos); a rotating pointer on the face of a timepiece; the (prehensile) extremity of the superior limb; ability; one of two sides of an issue; a round of applause to signify approval; the cards held in a card game by a given player at any given time; a position given by its location to the side of an object; a member of the crew of a ship; a unit of length equal to 4 inches; used in measuring horses; something written by hand; a card player in a game of bridge; a hired laborer on a farm or ranch; verb guide or conduct or usher somewhere; place into the hands or custody of
haploidy - the condition of being haploid
happiness - emotions experienced when in a state of well-being; state of well-being characterized by emotions ranging from contentment to intense joy
hard palate - the bony part of the roof of the mouth
hardness - the quality of being difficult to do; the property of being rigid and resistant to pressure; not easily scratched; measured on Mohs scale; excessive sternness; devoid of passion or feeling; hardheartedness
hay fever - a seasonal rhinitis resulting from an allergic reaction to pollen
headache - pain in the head caused by dilation of cerebral arteries or muscle contractions or a reaction to drugs; something or someone that causes anxiety; a source of unhappiness
health care - social insurance for the ill and injured; the preservation of mental and physical health by preventing or treating illness through services offered by the health profession
health insurance - insurance against loss due to ill health
health - the general condition of body and mind; a healthy state of wellbeing free from disease
hearing aid - a conical acoustic device formerly used to direct sound to the ear of a hearing-impaired person; an electronic device that amplifies sound and is worn to compensate for poor hearing
hearing disorder - impairment of the sense of hearing
hearing impairment - impairment of the sense of hearing
hearing - able to perceive sound; (law) a proceeding (usually by a court) where evidence is taken for the purpose of determining an issue of fact and reaching a decision based on that evidence; the ability to hear; the auditory faculty; a session (of a committee or grand jury) in which witnesses are called and testimony is taken; an opportunity to state your case and be heard; the act of hearing attentively; the range within which a voice can be heard
heart block - recurrent sudden attacks of unconsciousness caused by impaired conduction of the impulse that regulates the heartbeat
heart disease - a disease of the heart
heart failure - inability of the heart to pump enough blood to sustain normal bodily functions
heart murmur - an abnormal sound of the heart; sometimes a sign of abnormal function of the heart valves
heart rate - the rate at which the heart beats; usually measured to obtain a quick evaluation of a person's health
heart rhythm - the rhythm of a beating heart
heart surgery - any surgical procedure involving the heart
heart valve - an implant that replaces a natural cardiac valve; a valve to control one-way flow of blood
heart ventricle - a chamber of the heart that receives blood from an atrium and pumps it to the arteries
heart - a playing card in the major suit that has one or more red hearts on it; an inclination or tendency of a certain kind; the courage to carry on; the hollow muscular organ located behind the sternum and between the lungs; its rhythmic contractions move the blood through the body; the locus of feelings and intuitions; a firm rather dry variety meat (usually beef or veal); a plane figure with rounded sides curving inward at the top and intersecting at the bottom; conventionally used on playing cards and valentines; the choicest or most essential or most vital part of some idea or experience; a positive feeling of liking; an area that is approximately central within some larger region
heartburn - a painful burning sensation in the chest caused by gastroesophageal reflux (backflow from the stomach irritating the esophagus); symptomatic of an ulcer or a diaphragmatic hernia or other disorder
height - the vertical dimension of extension; distance from the base of something to the top; (of a standing person) the distance from head to foot; elevation especially above sea level or above the earth's surface; the highest level or degree attainable; the highest stage of development
helium - a very light colorless element that is one of the six inert gasses; the most difficult gas to liquefy; occurs in economically extractable amounts in certain natural gases (as those found in Texas and Kansas)
helminth - worm that is parasitic on the intestines of vertebrates especially roundworms and tapeworms and flukes
helminthiasis - infestation of the body with parasitic worms
hemangioma - benign angioma consisting of a mass of blood vessels; some appear as birthmarks
hematemesis - vomiting blood
hematochezia - passage of stools containing blood (as from diverticulosis or colon cancer or peptic ulcer)
hematocrit - a measuring instrument to determine (usually by centrifugation) the relative amounts of corpuscles and plasma in the blood; the ratio of the volume occupied by packed red blood cells to the volume of the whole blood as measured by a hematocrit
hematologist - a doctor who specializes in diseases of the blood and blood-forming organs
hematology - the branch of medicine that deals with diseases of the blood and blood-forming organs
hematoma - a localized swelling filled with blood
hematopoiesis - the formation of blood cells in the living body (especially in the bone marrow)
hematuria - the presence of blood in the urine; often a symptom of urinary tract disease
heme - a complex red organic pigment containing iron and other atoms to which oxygen binds
hemianopsia - blindness in one half of the visual field of one or both eyes
hemiplegia - paralysis of one side of the body
hemodialysis - dialysis of the blood to remove toxic substances or metabolic wastes from the bloodstream; used in the case of kidney failure
hemodynamics - the branch of physiology that studies the circulation of the blood and the forces involved
hemoglobin - a hemoprotein composed of globin and heme that gives red blood cells their characteristic color; function primarily to transport oxygen from the lungs to the body tissues
hemoglobinopathy - a blood disease characterized by the presence of abnormal hemoglobins in the blood
hemoglobinuria - presence of hemoglobin in the urine
hemolysin - any substance that can cause lysis (destruction) of erythrocytes (red blood cells) and the release of their hemoglobin
hemolysis - lysis of erythrocytes with the release of hemoglobin
hemolytic anemia - anemia resulting from destruction of erythrocytes
hemophilia a - hemophilia caused by a congenital deficiency of factor VIII; occurs almost exclusively in men
hemophilia b - a clotting disorder similar to hemophilia A but caused by a congenital deficiency of factor IX
hemophilia - congenital tendency to uncontrolled bleeding; usually affects males and is transmitted from mother to son
hemoprotein - a conjugated protein linked to a compound of iron and porphyrin
hemoptysis - coughing up blood from the respiratory tract; usually indicates a severe infection of the bronchi or lungs
hemorrhage - flow of blood from a ruptured blood vessels; verb lose blood from one's body
hemorrhoid - pain caused by venous swelling at or inside the anal sphincter
hemosiderosis - abnormal deposit of hemosiderin; often a symptom of thalassemia or hemochromatosis
hemostasis - surgical procedure of stopping the flow of blood (as with a hemostat)
hemothorax - accumulation of blood in the pleural cavity (the space between the lungs and the walls of the chest)
heparin - a polysaccharide produced in basophils (especially in the lung and liver) and that inhibits the activity of thrombin in coagulation of the blood; it (trade names Lipo-Hepin and Liquaemin) is used as an anticoagulant in the treatment of thrombosis and in heart surgery
hepatic artery - arteries that supply the liver
hepatic - pertaining to or affecting the liver; any of numerous small green nonvascular plants of the class Hepaticopsida growing in wet places and resembling green seaweeds or leafy mosses
hepatitis a virus - the virus causing hepatitis A
hepatitis a - an acute but benign form of viral hepatitis caused by an RNA virus that does not persist in the blood serum and is usually transmitted by ingesting food or drink that is contaminated with fecal matter
hepatitis b - an acute (sometimes fatal) form of viral hepatitis caused by a DNA virus that tends to persist in the blood serum and is transmitted by sexual contact or by transfusion or by ingestion of contaminated blood or other bodily fluids
hepatitis c - a viral hepatitis clinically indistinguishable from hepatitis B but caused by a single-stranded RNA virus; usually transmitted by parenteral means (as injection of an illicit drug or blood transfusion or exposure to blood or blood products)
hepatitis - inflammation of the liver caused by a virus or a toxin
hepatocellular carcinoma - carcinoma of the liver
hepatomegaly - abnormal enlargement of the liver
hereditary - inherited or inheritable by established rules (usually legal rules) of descent; tending to occur among members of a family usually by heredity
hermaphroditism - congenital condition in which external genitalia and internal sex organs have both male and female characteristics; showing characteristics of both sexes
hernia - rupture in smooth muscle tissue through which a bodily structure protrudes
heroin - a narcotic that is considered a hard drug; a highly addictive morphine derivative; intravenous injection provides the fastest and most intense rush
herpes encephalitis - common form of acute encephalitis caused by herpes simplex 1; usually affects the temporal and frontal lobes
herpes labialis - caused by herpes simplex virus type 1 (HSV-1)
heterocyclic compound - a compound containing a heterocyclic ring
heterogeneity - the quality of being diverse and not comparable in kind
heterophile antibody - an antibody found in the blood of someone suffering from infectious mononucleosis
hexachlorophene - antibacterial substance that is a water-soluble powder used in antiseptic soaps and toothpaste
hexanoic acid - a fatty acid found in animal oils and fats or made synthetically; smells like goats
hexestrol - estrogen compound used to treat menstrual irregularities and menopausal symptoms and to prevent pregnancy
hexose - a monosaccharide that contains six carbon atoms per molecule
hiatus hernia - hernia resulting from the protrusion of part of the stomach through the diaphragm
hibernation - the act of retiring into inactivity; cessation from or slowing of activity during the winter; especially slowing of metabolism in some animals; the torpid or resting state in which some animals pass the winter
hiccup - (usually plural) the state of having reflex spasms of the diaphragm accompanied by a rapid closure of the glottis producing an audible sound; sometimes a symptom of indigestion; verb breathe spasmodically, and make a sound
hilar - of or relating to or located near a hilum
hind - located at or near the back of an animal; female red deer; any of several mostly spotted fishes that resemble groupers
hip joint - the ball-and-socket joint between the head of the femur and the acetabulum
hip - informed about the latest trends; either side of the body below the waist and above the thigh; the ball-and-socket joint between the head of the femur and the acetabulum; the fruit of a rose plant; the structure of the vertebrate skeleton supporting the lower limbs in humans and the hind limbs or corresponding parts in other vertebrates
hippocampus - seahorses; a complex neural structure (shaped like a sea horse) consisting of grey matter and located on the floor of each lateral ventricle; intimately involved in motivation and emotion as part of the limbic system; has a central role in the formation of memories
hirsutism - excessive hairiness
histamine - amine formed from histidine that stimulates gastric secretions and dilates blood vessels; released by the human immune system during allergic reactions
histidine - an essential amino acid found in proteins that is important for the growth and repair of tissue
histiocytosis - a blood disease characterized by an abnormal multiplication of macrophages
histocompatibility - condition in which the cells of one tissue can survive in the presence of cells of another tissue
histology - the branch of biology that studies the microscopic structure of animal or plant tissues
histone - a simple protein containing mainly basic amino acids; present in cell nuclei in association with nucleic acids
hoarseness - a throaty harshness
hodgkin's disease - a malignant disorder in which there is progressive (but painless) enlargement of lymph tissue followed by enlargement of the spleen and liver
holography - the branch of optics that deals with the use of coherent light from a laser in order to make a hologram that can then be used to create a three-dimensional image
homeobox gene - one of various similar homeotic genes that are involved in bodily segmentation during embryonic development
homeopathy - a method of treating disease with small amounts of remedies that, in large amounts in healthy people, produce symptoms similar to those being treated
homeostasis - (physiology) metabolic equilibrium actively maintained by several complex biological mechanisms that operate via the autonomic nervous system to offset disrupting changes
homicide - the killing of a human being by another human being
hordeolum - an infection of the sebaceous gland of the eyelid
hormone replacement therapy - hormones (estrogen and progestin) are given to postmenopausal women; believed to protect them from heart disease and osteoporosis
hormone - the secretion of an endocrine gland that is transmitted by the blood to the tissue on which it has a specific effect
horner's syndrome - a pattern of symptoms occurring as a result of damage to nerves in the cervical region of the spine (drooping eyelids and constricted pupils and absence of facial sweating)
horseradish peroxidase - an enzyme used in immunohistochemistry to label antigens and their antibodies
hospice - a program of medical and emotional care for the terminally ill; a lodging for travelers (especially one kept by a monastic order)
hospital - a health facility where patients receive treatment; a medical institution where sick or injured people are given medical or surgical care
hospitalization - placing in medical care in a hospital; the condition of being treated as a patient in a hospital; a period of time when you are confined to a hospital; insurance that pays all or part of a patient's hospital expense
host - an animal or plant that nourishes and supports a parasite; it does not benefit and is often harmed by the association; a technical name for the bread used in the service of Mass or Holy Communion; archaic terms for army; any organization that provides resources and facilities for a function or event; the owner or manager of an inn; a person who invites guests to a social event (such as a party in his or her own home) and who is responsible for them while they are there; (medicine) recipient of transplanted tissue or organ from a donor; (computer science) a computer that provides client stations with access to files and printers as shared resources to a computer network; a vast multitude; a person who acts as host at formal occasions (makes an introductory speech and introduces other speakers); verb be the host of or for
hostility - a hostile (very unfriendly) disposition; the feeling of a hostile person; a state of deep-seated ill-will; violent action that is hostile and usually unprovoked
hot flash - sudden brief sensation of heat (associated with menopause and some mental disorders)
household - a social unit living together
human immunodeficiency virus - the virus that causes acquired immune deficiency syndrome (AIDS); it replicates in and kills the helper T cells
humerus - bone extending from the shoulder to the elbow
hunger - strong desire for something (not food or drink); a physiological need for food; the consequence of food deprivation; verb feel the need to eat; be hungry; go without food; have a craving, appetite, or great desire for
huntington's disease - hereditary disease; develops in adulthood and ends in dementia
husband - a married man; a woman's partner in marriage; verb use cautiously and frugally
hyaline cartilage - translucent cartilage that is common in joints and the respiratory passages; forms most of the fetal skeleton
hyaline - resembling glass in transparency or translucency; a glassy translucent material that occurs in hyaline cartilage or in certain skin conditions
hyaluronic acid - a viscous mucopolysaccharide found in the connective tissue space and the synovial fluid of movable joints and the humors of the eye; a cementing and protective substance
hybridoma - a hybrid cell resulting from the fusion of a lymphocyte and a tumor cell; used to culture a specific monoclonal antibody
hydatidiform mole - an abnormality during pregnancy; chorionic villi around the fetus degenerate and form clusters of fluid-filled sacs; usually associated with the death of the fetus
hydralazine - an antihypertensive drug (trade name Apresoline) that dilates blood vessels; used (often with a diuretic) to treat hypertension and congestive heart failure
hydrarthrosis - inflammation and swelling of a movable joint because of excess synovial fluid
hydrazine - a colorless fuming corrosive liquid; a powerful reducing agent; used chiefly in rocket fuels
hydrocarbon - an organic compound containing only carbon and hydrogen
hydrocephalus - an abnormal condition in which cerebrospinal fluid collects in the ventricles of the brain; in infants it can cause abnormally rapid growth of the head and bulging fontanelles and a small face; in adults the symptoms are primarily neurological
hydrochloric acid - an aqueous solution of hydrogen chloride; a strongly corrosive acid
hydrochlorothiazide - a diuretic drug (trade name Esidrix and HydroDIURIL) used in the treatment of hypertension
hydroflumethiazide - diuretic used to treat hypertension and edema
hydrogen ion concentration - the number of moles of hydrogen ions per cubic decimeter
hydrogen peroxide - a viscous liquid with strong oxidizing properties; a powerful bleaching agent; also used as a disinfectant and (in strong concentrations) as an oxidant in rocket fuels
hydrogen - a nonmetallic univalent element that is normally a colorless and odorless highly flammable diatomic gas; the simplest and lightest and most abundant element in the universe
hydromorphone - a narcotic analgesic (trade name Dilaudid) used to treat moderate to severe pain
hydronephrosis - accumulation of urine in the kidney because of an obstruction in the ureter
hydrothorax - accumulation of fluid in the pleural cavity (the space between the lungs and the walls of the chest) often resulting from disease of the heart or kidneys
hydroxychloroquine - anti-inflammatory drug (trade name Plaquenil) used in the treatment of rheumatoid arthritis and malaria and lupus erythematosus
hydroxyl group - the monovalent group -OH in such compounds as bases and some acids and alcohols
hydroxyl radical - the monovalent group -OH in such compounds as bases and some acids and alcohols
hydroxyproline - a crystalline amino acid obtained from gelatin or collagen
hydroxyzine - a drug (trade names Atarax and Vistaril) used as a tranquilizer to treat anxiety and motion sickness
hygiene - the science concerned with the prevention of illness and maintenance of health; a condition promoting sanitary practices
hymenoptera - an order of insects including: bees; wasps; ants; ichneumons; sawflies; gall wasps; etc.
hyoscyamine - a poisonous crystalline alkaloid (isometric with atropine but more potent); used to treat excess motility of the gastrointestinal tract
hyperactivity - a condition characterized by excessive restlessness and movement
hyperacusis - abnormal acuteness of hearing due to increased irritability of the sensory neural mechanism; characterized by intolerance for ordinary sound levels
hyperaldosteronism - a condition caused by overproduction of aldosterone
hyperbaric chamber - a large chamber in which the oxygen pressure is above normal for the atmosphere; used in treating breathing disorders or carbon monoxide poisoning
hyperbilirubinemia - abnormally high amounts of bile pigment (bilirubin) in the blood
hypercalcemia - the presence of abnormally high levels of calcium in the blood; usually the result of excessive bone resorption in hyperparathyroidism or Paget's disease
hypercalciuria - the presence of abnormally high levels of calcium in the urine; usually the result of excessive bone resorption in hyperparathyroidism or osteoporosis
hypercapnia - the presence of an abnormally high level of carbon dioxide in the circulating blood
hypercholesterolemia - the presence of an abnormal amount of cholesterol in the cells and plasma of the blood; associated with the risk of atherosclerosis
hyperemesis gravidarum - hyperemesis during pregnancy; if severe it can result in damage to the brain and liver and kidney
hyperemia - increased blood in an organ or other body part
hyperextension - greater than normal extension
hyperglycemia - abnormally high blood sugar usually associated with diabetes
hyperhidrosis - excessive and profuse perspiration
hypericum perforatum - yellow-flowered perennial common in fields and waste places but a weed in rangelands
hyperkalemia - higher than normal levels of potassium in the circulating blood; associated with kidney failure or sometimes with the use of diuretic drugs
hyperlipidemia - presence of excess lipids in the blood
hyperlipoproteinemia - any of various disorders of lipoprotein and cholesterol metabolism that result in high levels of lipoprotein and cholesterol in the circulating blood
hypernatremia - excessive amounts of sodium in the blood; possibly indicating diabetes insipidus
hyperopia - abnormal condition in which vision for distant objects is better than for near objects
hyperparathyroidism - excessive secretion of parathyroid hormone resulting in abnormally high levels of calcium in the blood; can affect many systems of the body (especially causing bone resorption and osteoporosis)
hyperpituitarism - excessive activity of the pituitary gland (especially overactivity of the anterior lobe which leads to excess secretion of growth hormone)
hyperplasia - abnormal increase in number of cells
hypersensitivity - extreme sensitivity; pathological sensitivity
hypersomnia - an inability to stay awake
hypersplenism - enlarged spleen and a decrease in one or more types of blood cells; associated with many disorders
hypertension - a common disorder in which blood pressure remains abnormally high (a reading of 140/90 mm Hg or greater)
hyperthyroidism - an overactive thyroid gland; pathologically excessive production of thyroid hormones or the condition resulting from excessive production of thyroid hormones
hypertonia - (of muscular tissue) the state of being hypertonic
hypertrophy - abnormal enlargement of a body part or organ; verb undergo hypertrophy
hyperventilation - an increased depth and rate of breathing greater than demanded by the body needs; can cause dizziness and tingling of the fingers and toes and chest pain if continued
hypervolemia - a blood disorder consisting of an increase in the volume of circulating blood
hypha - any of the threadlike filaments forming the mycelium of a fungus
hyphema - bleeding into the interior chamber of the eye
hypnosis - a state that resembles sleep but that is induced by suggestion
hypnotherapy - the use of hypnosis in psychotherapy
hypoadrenalism - a glandular disorder caused by failure of function of the cortex of the adrenal gland and marked by anemia and prostration with brownish skin
hypoblast - the inner germ layer that develops into the lining of the digestive and respiratory systems
hypocalcemia - abnormally low level of calcium in the blood; associated with hypoparathyroidism or kidney malfunction or vitamin D deficiency
hypocapnia - a state in which the level of carbon dioxide in the blood is lower than normal; can result from deep or rapid breathing
hypochondriasis - chronic and abnormal anxiety about imaginary symptoms and ailments
hypochromic anemia - anemia characterized by a decrease in the concentration of corpuscular hemoglobin
hypodermic needle - a hollow needle
hypoesthesia - impairment of tactile sensitivity; decrease of sensitivity
hypogammaglobulinemia - an abnormally low concentration of gamma globulin in the blood and increased risk of infection
hypoglossal nerve - supplies intrinsic muscles of the tongue and other tongue muscles
hypoglycemia - abnormally low blood sugar usually resulting from excessive insulin or a poor diet
hypoglycemic agent - any of various agents that decrease the level of glucose in the blood and are used in the treatment of diabetes mellitus
hypogonadism - incompetence of the gonads (especially in the male with low testosterone); results in deficient development of secondary sex characteristics and (in prepubertal males) a body with long legs and a short trunk
hypokalemia - abnormally low level of potassium in the circulating blood leading to weakness and heart abnormalities; associated with adrenal tumors or starvation or taking diuretics
hypolipoproteinemia - any of various disorders of lipoprotein and cholesterol metabolism that result in low levels of lipoprotein and cholesterol in the circulating blood
hyponatremia - abnormally low level of sodium in the blood; associated with dehydration
hypoparathyroidism - inadequate secretion of parathyroid hormone resulting in abnormally low levels of calcium in the blood
hypophysectomy - surgical removal of the pituitary gland
hypoplasia - underdevelopment of an organ because of a decrease in the number of cells
hypopnea - slow or shallow breathing
hypoproteinemia - abnormally low level of protein in the blood; can indicate inadequate diet or intestinal or renal disorders
hyposmia - lessened sensitivity to odors
hypospadias - an abnormal condition in males in which the urethra opens on the under surface of the penis
hypotension - abnormally low blood pressure
hypothalamus - a basal part of the diencephalon governing autonomic nervous system
hypothermia - subnormal body temperature
hypothyroidism - an underactive thyroid gland; a glandular disorder resulting from insufficient production of thyroid hormones
hypotonia - (of muscular tissue) the state of being hypotonic
hypovolemia - a blood disorder consisting of a decrease in the volume of circulating blood
hypovolemic shock - shock caused by severe blood or fluid loss
hypoxia - a very strong drive resulting from a deficiency of available oxygen in the blood and bodily tissues (short of anoxia)
hysterectomy - surgical removal of the uterus
hysteria - excessive or uncontrollable fear; neurotic disorder characterized by violent emotional outbreaks and disturbances of sensory and motor functions; state of violent mental agitation
hysterotomy - surgical incision into the uterus (as in cesarean section)
ibuprofen - a nonsteroidal anti-inflammatory medicine (trade names Advil and Motrin and Nuprin) used to relieve the pain of arthritis and as an analgesic and antipyretic
ichthyosis - any of several congenital diseases in which the skin is fishlike (dry and scaly)
ileitis - inflammation of the ileum
ileocecal valve - valve between the ileum of the small intestine and the cecum of the large intestine; prevents material from flowing back from the large to the small intestine
ileum - the part of the small intestine between the jejunum and the cecum
ileus - blockage of the intestine (especially the ileum) that prevents the contents of the intestine from passing to the lower bowel
iliac artery - one of the large arteries supplying blood to the pelvis and legs
iliac vein - one of three veins draining the pelvic area
illusion - something many people believe that is false; an erroneous mental representation; an illusory feat; considered magical by naive observers; the act of deluding; deception by creating illusory ideas
imagination - the formation of a mental image of something that is not perceived as real and is not present to the senses; the ability to form mental images of things or events; the ability to deal resourcefully with unusual problems
imaging - (medicine) obtaining pictures of the interior of the body; the ability to form mental images of things or events
imide - any of a class of organic compounds that contain the divalent radical -CONHCO-
imipramine - a tricyclic antidepressant (trade names Imavate and Tofranil) used to treat clinical depression
immature - lacking in development; not yet mature; characteristic of a lack of maturity; (of birds) not yet having developed feathers; not fully developed or mature; not ripe; (used of living things especially persons) in an early period of life or development or growth
immobilization - the act of limiting movement or making incapable of movement; fixation (as by a plaster cast) of a body part in order to promote proper healing
immune response - a bodily defense reaction that recognizes an invading substance (an antigen: such as a virus or fungus or bacteria or transplanted organ) and produces antibodies specific against that antigen
immune system - a system (including the thymus and bone marrow and lymphoid tissues) that protects the body from foreign substances and pathogenic organisms by producing the immune response
immunity - the quality of being unaffected by something; (medicine) the condition in which an organism can resist disease; an act exempting someone; the state of not being susceptible
immunization - the act of making immune (especially by inoculation)
immunochemistry - the field of chemistry concerned with chemical processes in immunology (such as chemical studies of antigens and antibodies)
immunocompetence - the ability to develop an immune response following exposure to an antigen
immunodeficiency - immunological disorder in which some part of the body's immune system is inadequate and resistance to infectious diseases is reduced
immunoelectrophoresis - electrophoresis to separate antigens and antibodies
immunoglobulin a - one of the most common of the five major classes of immunoglobulins; the chief antibody in the membranes of the gastrointestinal and respiratory tracts
immunoglobulin d - one of the five major classes of immunoglobulins; present in blood serum in small amounts
immunoglobulin e - one of the five major classes of immunoglobulins; present primarily in the skin and mucous membranes
immunoglobulin g - one of the five major classes of immunoglobulins; the main antibody defense against bacteria
immunoglobulin m - one of the five major classes of immunoglobulins; involved in fighting blood infections and in triggering production of immunoglobulin G
immunoglobulin - a class of proteins produced in lymph tissue in vertebrates and that function as antibodies in the immune response
immunohistochemistry - an assay that shows specific antigens in tissues by the use of markers that are either fluorescent dyes or enzymes (such as horseradish peroxidase)
immunology - the branch of medical science that studies the body's immune system
immunosuppressive - of or relating to a substance that lowers the body's normal immune response and induces immunosuppression; a drug that lowers the body's normal immune response
immunotherapy - therapy designed to produce immunity to a disease or to enhance resistance by the immune system
impacted tooth - a disorder in which a tooth is so crowded in its socket that it cannot erupt normally
impetigo - a very contagious infection of the skin; common in children; localized redness develops into small blisters that gradually crust and erode
implant - a prosthesis placed permanently in tissue; verb become attached to and embedded in the uterus; fix or set securely or deeply; put firmly in the mind
impotence - an inability (usually of the male animal) to copulate; the quality of lacking strength or power; being weak and feeble
in-situ - being in the original position; not having been moved
incidence - the striking of a light beam on a surface; the relative frequency of occurrence of something
incisor - a tooth for cutting or gnawing; located in the front of the mouth in both jaws
inclusion body - any small intracellular body found within another (characteristic of certain diseases)
incontinence - involuntary urination or defecation; indiscipline with regard to sensuous pleasures
indapamide - diuretic (trade name Lozal) used in the treatment of hypertension
indeterminate - not leading to a definite ending or result; not capable of being determined; not precisely determined or established; not fixed or known in advance; having a capacity for continuing to grow at the apex; of uncertain or ambiguous nature
indication - something (as a course of action) that is indicated as expedient or necessary; something that serves to indicate or suggest; (medicine) a reason to prescribe a drug or perform a procedure; the act of indicating or pointing out by name; a datum about some physical state that is presented to a user by a meter or similar instrument
indinavir - a protease inhibitor (trade name Crixivan) used for treating HIV
indium - a rare soft silvery metallic element; occurs in small quantities in sphalerite
indolent - (of tumors e.g) slow to heal or develop and usually painless; disinclined to work or exertion
indomethacin - a nonsteroidal anti-inflammatory drug (trade name Indocin)
induced abortion - a deliberate termination of pregnancy
infant mortality - the death rate during the first year of life
infant - a very young child (birth to 1 year) who has not yet begun to walk or talk
infarct - localized necrosis resulting from obstruction of the blood supply
infection - (international law) illegality that taints or contaminates a ship or cargo rendering it liable to seizure; moral corruption or contamination; an incident in which an infectious disease is transmitted; (medicine) the invasion of the body by pathogenic microorganisms and their multiplication which can lead to tissue damage and disease; (phonetics) the alteration of a speech sound under the influence of a neighboring sound; the pathological state resulting from the invasion of the body by pathogenic microorganisms; the communication of an attitude or emotional state among a number of people
inferior colliculus - an essential auditory center in the midbrain
inferior vena cava - receives blood from lower limbs and abdominal organs and empties into the posterior part of the right atrium of the heart; formed from the union of the two iliac veins
inferior - of or characteristic of low rank or importance; of low or inferior quality; having an orbit between the sun and the Earth's orbit; lower than a given reference point; inferior in rank or status; falling short of some prescribed norm; written or printed below and to one side of another character; one of lesser rank or station or quality; a character or symbol set or printed or written beneath or slightly below and to the side of another character
infertility - the state of being unable to produce offspring; in a woman it is an inability to conceive; in a man it is an inability to impregnate
infiltration - a process in which individuals (or small groups) penetrate an area (especially the military penetration of enemy positions without detection); the slow passage of a liquid through a filtering medium
inflammation - arousal to violent emotion; a response of body tissues to injury or irritation; characterized by pain and swelling and redness and heat; the act of setting something on fire; the state of being emotionally aroused and worked up
inflammatory bowel disease - inflammation of the colon
infliximab - an anti-TNF compound (trade name Remicade) consisting of an antibody directed against TNF; it is given intravenously at one-month to three-month intervals; used in treatment of regional enteritis and rheumatoid arthritis
influenza - an acute febrile highly contagious viral disease
informatics - the sciences concerned with gathering, manipulating, storing, retrieving, and classifying recorded information
informative - providing or conveying information; serving to instruct of enlighten or inform; tending to increase knowledge or dissipate ignorance
informed consent - consent by a patient to undergo a medical or surgical treatment or to participate in an experiment after the patient understands the risks involved
ingestion - the process of taking food into the body through the mouth (as by eating)
ingredient - a component of a mixture or compound; food that is a component of a mixture in cooking; an abstract part of something
inguinal hernia - hernia in which a loop of intestine enters the inguinal canal; the most common type of hernia in males
inhalation - the act of inhaling; the drawing in of air (or other gases) as in breathing; a medication to be taken by inhaling it
inhaler - a dispenser that produces a chemical vapor to be inhaled in order to relieve nasal congestion
injection - the forceful insertion of a substance under pressure; the act of putting a liquid into the body by means of a syringe; any solution that is injected (as into the skin)
innate immunity - immunity to disease that occurs as part of an individual's natural biologic makeup
inoperable - not suitable for surgery; not able to perform its normal function
inosine - a nucleoside that is formed by the deamination of adenosine; used in kidney transplantation to provide a temporary source of sugar
inositol - an optically inactive alcohol that is a component of the vitamin B complex
inpatient - a patient who is residing in the hospital where he is being treated
insecta - insects; about five-sixths of all known animal species
insemination - the introduction of semen into the genital tract of a female; the act of sowing (of seeds in the ground or, figuratively, of germs in the body or ideas in the mind, etc.)
instance - an item of information that is representative of a type; an occurrence of something; verb clarify by giving an example of
instinct - (followed by `with')deeply filled or permeated; inborn pattern of behavior often responsive to specific stimuli
insulin shock - the administration of sufficient insulin to induce convulsions and coma; hypoglycemia produced by excessive insulin in the system causing coma
insulin - hormone secreted by the isles of Langerhans in the pancreas; regulates storage of glycogen in the liver and accelerates oxidation of sugar in cells
insurance - promise of reimbursement in the case of loss; paid to people or companies so concerned about hazards that they have made prepayments to an insurance company; written contract or certificate of insurance; protection against future loss
integumentary system - the skin and its appendages
intelligence test - a psychometric test of intelligence
intelligence - the operation of gathering information about an enemy; the ability to comprehend; to understand and profit from experience; secret information about an enemy (or potential enemy); a unit responsible for gathering and interpreting information about an enemy; new information about specific and timely events
intensive care - close monitoring and constant medical care of patients with life-threatening conditions
interferon - an antiviral protein produced by cells that have been invaded by a virus; inhibits replication of the virus
interleukin - any of several lymphokines that promote macrophages and killer T cells and B cells and other components of the immune system
interleukin - any of several lymphokines that promote macrophages and killer T cells and B cells and other components of the immune system
interlocutory - consisting of dialogue
intermediate - lying between two extremes in time or space or degree; around the middle of a scale of evaluation of physical measures; a substance formed during a chemical process before the desired product is obtained; verb act between parties with a view to reconciling differences
intermittent claudication - lameness due to pain in leg muscles because the blood supply is inadequate; pain subsides with rest
internal - happening or arising or located within some limits or especially surface; occurring within an institution or community; located inward; inside the country; innermost or essential
internist - a specialist in internal medicine
interstitial fluid - liquid found between the cells of the body that provides much of the liquid environment of the body
intervertebral disk - a fibrocartilaginous disc serving as a cushion between all of the vertebrae of the spinal column (except between the first two)
intestine - the part of the alimentary canal between the stomach and the anus
intoxication - excitement and elation beyond the bounds of sobriety; a temporary state resulting from excessive consumption of alcohol; the physiological state produced by a poison or other toxic substance
intracerebral - within the brain
intracranial aneurysm - an aneurysm of a cranial artery
intramuscular injection - an injection into a muscle
intrauterine device - contraceptive device consisting of a piece of bent plastic or metal that is inserted through the vagina into the uterus
intravenous pyelogram - X-ray picture of the kidneys and ureters after injection of a radiopaque dye
intrinsic factor - a substance produced by the mucosa of the stomach and intestines that is essential for the absorption of vitamin B12
intron - sequence of a eukaryotic gene's DNA that is not translated into a protein
intubation - the insertion of a cannula or tube into a hollow body organ
intussusception - (biology) growth in the surface area of a cell by the deposit of new particles between existing particles in the cell wall; the folding in of an outer layer so as to form a pocket in the surface
inulin - used to manufacture fructose and in assessing kidney function
iodide - a salt or ester of hydriodic acid
iodine - a nonmetallic element belonging to the halogens; used especially in medicine and photography and in dyes; occurs naturally only in combination in small quantities (as in sea water or rocks); a tincture consisting of a solution of iodine in ethyl alcohol; applied topically to wounds as an antiseptic
ion - a particle that is electrically charged (positive or negative); an atom or molecule or group that has lost or gained one or more electrons
iontophoresis - therapy that uses a local electric current to introduce the ions of a medicine into the tissues
ipsilateral - on or relating to the same side (of the body)
iridium - a heavy brittle metallic element of the platinum group; used in alloys; occurs in natural alloys with platinum or osmium
iridocyclitis - inflammation of the iris and ciliary body of the eye
iris - diaphragm consisting of thin overlapping plates that can be adjusted to change the diameter of a central opening; muscular diaphragm that controls the size of the pupil; it forms the colored portion of the eye; plants with sword-shaped leaves and erect stalks bearing bright-colored flowers composed of three petals and three drooping sepals
iritis - inflammation of the iris
iron overload - pathology in which iron accumulates in the tissues; characterized by bronzed skin and enlarged liver and diabetes mellitus and abnormalities of the pancreas and the joints
iron - extremely robust; home appliance consisting of a flat metal base that is heated and used to smooth cloth; a golf club that has a relatively narrow metal head; implement used to brand live stock; a heavy ductile magnetic metallic element; is silver-white in pure form but readily rusts; used in construction and tools and armament; plays a role in the transport of oxygen by the blood; verb press and smooth with a heated iron
irritable bowel syndrome - recurrent abdominal pain and diarrhea (often alternating with periods of constipation); often associated with emotional stress
ischemia - local anemia in a given body part sometimes resulting from vasoconstriction or thrombosis or embolism
ischium - one of the three sections of the hipbone; situated below the ilium
isocarboxazid - a monoamine oxidase inhibitor (trade name Marplan) that is used to treat clinical depression
isocyanate - a salt or ester of isocyanic acid
isoflurane - a widely used inhalation anesthetic
isoleucine - an essential amino acid found in proteins; isomeric with leucine
isomerase - an enzyme that catalyzes its substrate to an isomeric form
isoniazid - antibacterial drug (trade name Nydrazid) used to treat tuberculosis
isopropyl alcohol - alcohol used as antifreeze or a solvent
isoproterenol - drug (trade name Isuprel) used to treat bronchial asthma and to stimulate the heart
isosorbide - drug (trade name Isordil) used to treat angina pectoris and congestive heart failure
isothiocyanate - a family of compounds derived from horseradish and radishes and onions and mustards; source of the hotness of those plants and preparations
isotonic solution - a solution having the same osmotic pressure as blood
isotope - one of two or more atoms with the same atomic number but with different numbers of neutrons
itraconazole - an oral antifungal drug (trade name Sporanox) taken for cases of fungal nail disease
jaundice - yellowing of the skin and the whites of the eyes caused by an accumulation of bile pigment (bilirubin) in the blood; can be a symptom of gallstones or liver infection or anemia; a rough and bitter manner; verb affect with, or as if with, jaundice; distort adversely
jaw - holding device consisting of one or both of the opposing parts of a tool that close to hold an object; the part of the skull of a vertebrate that frames the mouth and holds the teeth; the bones of the skull that frame the mouth and serve to open it; the bones that hold the teeth; verb censure severely or angrily; talk incessantly and tiresomely; talk socially without exchanging too much information; chew (food)
jejunum - the part of the small intestine between the duodenum and the ileum
joint - involving both houses of a legislature; united or combined; affecting or involving two or more; marijuana leaves rolled into a cigarette for smoking; junction by which parts or objects are joined together; a disreputable place of entertainment; (anatomy) the point of connection between two bones or elements of a skeleton (especially if it allows motion); a piece of meat roasted or for roasting and of a size for slicing into more than one portion; the shape or manner in which things come together and a connection is made; verb separate (meat) at the joint; fasten with a joint; provide with a joint; fit as if by joints
judaism - the monotheistic religion of the Jews having its spiritual and ethical principles embodied chiefly in the Torah and in the Talmud; Jews collectively who practice a religion based on the Torah and the Talmud
judgment - the act of judging or assessing a person or situation or event; (law) the determination by a court of competent jurisdiction on matters submitted to it; the capacity to assess situations or circumstances shrewdly and to draw sound conclusions; the cognitive process of reaching a decision or drawing conclusions; an opinion formed by judging something; the mental ability to understand and discriminate between relations; the legal document stating the reasons for a judicial decision
jugular vein - veins in the neck that return blood from the head
jumping gene - a segment of DNA that can become integrated at many different sites along a chromosome (especially a segment of bacterial DNA that can be translocated as a whole)
juvenile delinquency - an antisocial misdeed in violation of the law by a minor
kanamycin - antibiotic (trade name Kantrex) used to treat severe infections
kaposi's sarcoma - a sarcoma that starts with purplish spots on the feet and legs and spreads from the skin to lymph nodes and internal organs; a common manifestation of AIDS
kava - an alcoholic drink made from the aromatic roots of the kava shrub
keloid - raised pinkish scar tissue at the site of an injury; results from excessive tissue repair
keratin - a fibrous scleroprotein that occurs in the outer layer of the skin and in horny tissues such as hair feathers nails and hooves
keratitis - inflammation of the cornea causing watery painful eyes and blurred vision
keratoacanthoma - skin tumor that grows rapidly (especially in older people) and resembles a carcinoma but does not spread; it usually disappears spontaneously, often leaving a scar
keratoconjunctivitis - inflammation of the cornea and conjunctiva
keratoconus - abnormal cone-shaped protrusion of the cornea of the eye; can be treated by epikeratophakia
keratoplasty - a surgical procedure in which part or all of a damaged or diseased cornea is replaced by healthy corneal tissue from a donor
keratosis follicularis - a rare hereditary condition marked by dark crusted patches (sometimes containing pus)
keratosis - a skin condition marked by an overgrowth of layers of horny skin
kernicterus - an abnormal accumulation of bile pigment in the brain and other nerve tissue; causes yellow staining and tissue damage
ketamine hydrochloride - a general anesthetic and tranquilizer (not a barbiturate) that is administered intravenously or intramuscularly; used mainly by veterinarians or for minor surgery with geriatric or pediatric patients; taken in large doses it causes hallucinations similar to those associated with the use of PCP
ketamine - a general anesthetic and tranquilizer (not a barbiturate) that is administered intravenously or intramuscularly; used mainly by veterinarians or for minor surgery with geriatric or pediatric patients; taken in large doses it causes hallucinations similar to those associated with the use of PCP
ketone - any of a class of organic compounds having a carbonyl group linked to a carbon atom in each of two hydrocarbon radicals
ketonuria - excessive amounts of ketone bodies in the urine as in diabetes mellitus or starvation
ketoprofen - nonsteroidal anti-inflammatory drug (trade names Orudis or Orudis KT or Oruvail)
ketorolac tromethamine - nonsteroidal anti-inflammatory drug (trade names Acular and Toradol) that is administered only intramuscularly
ketorolac - nonsteroidal anti-inflammatory (trade name Torodal) that is given only orally
ketosis - an abnormal increase of ketone bodies in the blood as in diabetes mellitus
kidney disease - a disease affecting the kidneys
kidney - either of two bean-shaped excretory organs that filter wastes (especially urea) from the blood and excrete them and water in urine
kilogram - one thousand grams; the basic unit of mass adopted under the Systeme International d'Unites
kilometer - a metric unit of length equal to 1000 meters (or 0.621371 miles)
kinase - an enzyme that catalyzes the conversion of a proenzyme to an active enzyme
kinesis - a movement that is a response to a stimulus but is not oriented with respect to the source of stimulation
kinetochore - a specialized condensed region of each chromosome that appears during mitosis where the chromatids are held together to form an X shape
kinin - any of a class of plant hormones that promote cell division and delay the senescence of leaves
klebsiella - a genus of nonmotile rod-shaped Gram-negative enterobacteria; some cause respiratory and other infections
kleptomania - an irresistible impulse to steal in the absence of any economic motive
klinefelter's syndrome - syndrome in males that is characterized by small testes and long legs and enlarged breasts and reduced sperm production and mental retardation; a genetic defect in which an extra X chromosome (XXY) is present in the male
knee joint - hinge joint in the human leg connecting the tibia and fibula with the femur and protected in front by the patella
knee - the part of a trouser leg that provides the cloth covering for the knee; hinge joint in the human leg connecting the tibia and fibula with the femur and protected in front by the patella; joint between the femur and tibia in a quadruped; corresponds to the human knee
kyphosis - an abnormal backward curve to the vertebral column
labetalol - antihypertensive drug (trade names Trandate and Normodyne) that blocks alpha and beta-adrenergic receptors of the sympathetic nervous system (leading to a decrease in blood pressure)
labor pain - pain and discomfort associated with contractions of the uterus during labor
laboratory - a workplace for the conduct of scientific research; a region resembling a laboratory inasmuch as it offers opportunities for observation and practice and experimentation
labyrinth - complex system of paths or tunnels in which it is easy to get lost; a complex system of interconnecting cavities; concerned with hearing and equilibrium
lacrimal apparatus - the structures that secrete and drain tears from the eye
lacrimal gland - any of the glands in the eyes that secrete tears
lactase - any of a group of enzymes (trade name Lactaid) that hydrolyze lactose to glucose and galactose
lactate - a salt or ester of lactic acid; verb give suck to
lactation - the production and secretion of milk by the mammary glands; the period following birth during which milk is secreted; feeding an infant by giving suck at the breast
lactic acid - a clear odorless hygroscopic syrupy carboxylic acid found in sour milk and in many fruits
lactobacillaceae - lactic acid bacteria and important pathogens; bacteria that ferment carbohydrates chiefly into lactic acid
lactobacillus - Gram-positive rod-shaped bacteria that produce lactic acid especially in milk
lactose intolerance - congenital disorder consisting of an inability to digest milk and milk products; absence or deficiency of lactase results in an inability to hydrolyze lactose
lactose - a sugar comprising one glucose molecule linked to a galactose molecule; occurs only in milk
laetrile - a substance derived from amygdalin; publicized as an antineoplastic drug although there is no supporting evidence
laminectomy - surgical removal of the bony arches on one or more vertebrae
lamivudine - a nucleoside reverse transcriptase inhibitor that is very effective in combination with zidovudine in treating AIDS and HIV
lanolin - an emollient containing wool fat (a fatty substance obtained from the wool of sheep); a yellow viscous animal oil extracted from wool; a mixture of fatty acids and esters; used in some ointments and cosmetics
lansoprazole - antacid (trade name Prevacid) that suppresses acid secretion in the stomach
lanthanum - a white soft metallic element that tarnishes readily; occurs in rare earth minerals and is usually classified as a rare earth
lanugo - the fine downy hair covering a human fetus; normally shed during the ninth month of gestation
laparoscope - a slender endoscope inserted through an incision in the abdominal wall in order to examine the abdominal organs or to perform minor surgery
laparoscopy - laparotomy performed with a laparoscope that makes a small incision to examine the abdominal cavity (especially the ovaries and Fallopian tubes)
laparotomy - surgical incision into the abdominal wall; often done to examine abdominal organs
large intestine - beginning with the cecum and ending with the rectum; includes the cecum and the colon and the rectum; extracts moisture from food residues which are later excreted as feces
larva - the immature free-living form of most invertebrates and amphibians and fish which at hatching from the egg is fundamentally unlike its parent and must metamorphose
laryngectomy - surgical removal of part or all of the larynx (usually to treat cancer of the larynx)
laryngismus - laryngeal spasm caused by the sudden contraction of laryngeal muscles
laryngitis - inflammation of the mucous membrane of the larynx; characterized by hoarseness or loss of voice and coughing
laryngoscope - a medical instrument for examining the larynx
laryngostenosis - abnormal narrowing of the larynx
larynx - a cartilaginous structure at the top of the trachea; contains elastic vocal cords that are the source of the vocal tone in speech
lassa fever - an acute contagious viral disease of central western Africa; characterized by fever and inflammation and muscular pains and difficulty swallowing; can be used as a bioweapon
lassa virus - the RNA virus that causes Lassa fever
lassitude - weakness characterized by a lack of vitality or energy; a feeling of lack of interest or energy; a state of comatose torpor (as found in sleeping sickness)
lateral - lying away from the median and sagittal plane of a body; situated at or extending to the side; a pass to a receiver upfield from the passer
lauric acid - a crystalline fatty acid occurring as glycerides in natural fats and oils (especially coconut oil and palm-kernel oil)
laxative - stimulating evacuation of feces; a mild cathartic
lead poisoning - toxic condition produced by the absorption of excessive lead into the system
learning disorder - a disorder found in children of normal intelligence who have difficulties in learning specific skills
learning - the cognitive process of acquiring skill or knowledge; profound scholarly knowledge
lecithin - a yellow phospholipid essential for the metabolism of fats; found in egg yolk and in many plant and animal cells; used commercially as an emulsifier
lectin - any of several plant glycoproteins that act like specific antibodies but are not antibodies in that they are not evoked by an antigenic stimulus
leflunomide - an anti-TNF compound (trade name Arava) that is given orally; can slow the progression of rheumatoid arthritis by slowing the proliferation of white blood cells which reduces inflammation in the synovium
left atrium - the left upper chamber of the heart that receives blood from the pulmonary veins
left ventricle - the chamber on the left side of the heart that receives arterial blood from the left atrium and pumps it into the aorta
leg - (nautical) the distance traveled by a sailing vessel on a single tack; a cloth covering consisting of the part of a pair of trousers that covers a person's leg; one of the supports for a piece of furniture; a human limb; commonly used to refer to a whole limb but technically only the part of the limb between the knee and ankle; a structure in animals that is similar to a human leg and used for locomotion; the limb of an animal used for food; a section or portion of a journey or course; a prosthesis that replaces a missing leg; a part of a forked or branching shape
legionella - the motile aerobic rod-shaped Gram-negative bacterium that thrives in central heating and air conditioning systems and can cause Legionnaires' disease
legionnaires' disease - acute (sometimes fatal) lobar pneumonia caused by bacteria of a kind first recognized after an outbreak of the disease at an American Legion convention in Philadelphia in 1976; characterized by fever and muscle and chest pain and headache and chills and a dry cough
leiomyosarcoma - sarcoma of smooth muscle; occurs most often digestive tract or uterus or bladder or prostate
leishmania - flagellate protozoan that causes leishmaniasis
leishmaniasis - sores resulting from a tropical infection by protozoa of the genus Leishmania which are spread by sandflies
leisure - freedom to choose a pastime or enjoyable activity; time available for ease and relaxation
lens - a transparent optical device used to converge or diverge transmitted light and to form images; electronic equipment that uses a magnetic or electric field in order to focus a beam of electrons; biconvex transparent body situated behind the iris in the eye; it focuses light waves on the retina; (metaphor) a channel through which something can be seen or understood; genus of small erect or climbing herbs with pinnate leaves and small inconspicuous white flowers and small flattened pods: lentils
lentigo - a small brownish spot (of the pigment melanin) on the skin
lepidoptera - moths and butterflies
leprosy - chronic granulomatous communicable disease occurring in tropical and subtropical regions; characterized by inflamed nodules beneath the skin and wasting of body parts; caused by the bacillus Mycobacterium leprae
leptomeninges - the two innermost layers of the meninges; cerebrospinal fluid circulates between these innermost layers
leptospira - important pathogens causing Weil's disease or canicola fever
leptospirosis - an infectious disease cause by leptospira and transmitted to humans from domestic animals; characterized by jaundice and fever
lesion - any visible abnormal structural change in a bodily part; any break in the skin or an organ caused by violence or surgical incision
less than - comparing quantity or quality
lethargy - a state of comatose torpor (as found in sleeping sickness); inactivity; showing an unusual lack of energy; weakness characterized by a lack of vitality or energy
leucine - a white crystalline amino acid occurring in proteins that is essential for nutrition; obtained by the hydrolysis of most dietary proteins
leukemia - malignant neoplasm of blood-forming tissues; characterized by abnormal proliferation of leukocytes; one of the four major types of cancer
leukocyte - blood cells that engulf and digest bacteria and fungi; an important part of the body's defense system
leukocytosis - an abnormal increase in the number of white blood cells in the blood as a result of infection (as in leukemia)
leukopenia - an abnormal lowering of the white blood cell count
leukorrhea - discharge of white mucous material from the vagina; often an indication of infection
levodopa - the levorotatory form of dopa (trade names Bendopa and Brocadopa and Larodopa); as a drug it is used to treat Parkinson's disease
leydig cell - a cell in the testes that secretes the hormone testosterone
libido - (psychoanalysis) a Freudian term for sexual urge or desire
lichen planus - an eruption of shiny flat-topped purplish (usually itchy) papules on the wrist and forearms and thighs
lidocaine - a local anesthetic (trade names Lidocaine and Xylocaine) used topically on the skin and mucous membranes
life - living things collectively; the experience of being alive; the course of human events and activities; a motive for living; a living person; the organic phenomenon that distinguishes living organisms from nonliving ones; the course of existence of an individual; the actions and events that occur in living; a characteristic state or mode of living; the period during which something is functional (as between birth and death); the period between birth and the present time; the period from the present until death; animation and energy in action or expression; an account of the series of events making up a person's life; the condition of living or the state of being alive; a prison term lasting as long as the prisoner lives
ligament - any connection or unifying bond; a sheet or band of tough fibrous tissue connecting bones or cartilages or supporting muscles or organs
ligand - an atom or molecule or radical or ion that forms a complex around a central atom
ligation - (surgery) tying a duct or blood vessel with a ligature (as to prevent bleeding during surgery)
light microscope - microscope consisting of an optical instrument that magnifies the image of an object
lignin - a complex polymer; the chief constituent of wood other than carbohydrates; binds to cellulose fibers to harden and strengthen cell walls of plants
limb - the graduated arc that is attached to an instrument for measuring angles; either of the two halves of a bow from handle to tip; one of the jointed appendages of an animal used for locomotion or grasping: arm; leg; wing; flipper; (astronomy) the circumferential edge of the apparent disc of the sun or the moon or a planet; any of the main branches arising from the trunk or a bough of a tree; any projection that is thought to resemble a human arm
limbic system - a system of functionally related neural structures in the brain that are involved in emotional behavior
lincomycin - antibiotic (trade name Lincocin) obtained from a streptomyces bacterium and used in the treatment of certain penicillin-resistant infections
lindane - a white crystalline powder used as an agricultural insecticide
liniment - a medicinal liquid that is rubbed into the skin to relieve muscular stiffness and pain
linoleic acid - a liquid polyunsaturated fatty acid abundant in plant fats and oils; a fatty acid essential for nutrition; used to make soap
linolenic acid - a liquid polyunsaturated fatty acid that occurs in some plant oils; an essential fatty acid
linseed oil - a drying oil extracted from flax seed and used in making such things as oil paints
lip - fleshy folds of tissue as those surrounding the mouth; the top edge of a vessel or other container; an impudent or insolent rejoinder
lipase - an enzyme secreted in the digestive tract that catalyzes the breakdown of fats into individual fatty acids that can be absorbed into the bloodstream
lipid - an oily organic compound insoluble in water but soluble in organic solvents; essential structural component of living cells (along with proteins and carbohydrates)
lipoma - a tumor consisting of fatty tissue
lipoprotein - a conjugated protein having a lipid component; the principal means for transporting lipids in the blood
liposarcoma - sarcoma of fat cells
liposome - an artificially made microscopic vesicle into which nucleic acids can be packaged; used in molecular biology as a transducing vector
liquid crystal - a liquid exhibiting properties of a crystal that are not shown by ordinary liquids
lisinopril - an ACE inhibiting drug (trade names Prinival or Zestril) administered as an antihypertensive and after heart attacks
listeria monocytogenes - the type species of the genus Listeria; can cause meningitis, encephalitis, septicemia, endocarditis, abortion, abscesses, listeriosis
listeria - any species of the genus Listeria
listeriosis - an infectious disease of animals and humans (especially newborn or immunosuppressed persons) caused by the bacterium Listeria monocytogenes; in sheep and cattle the infection frequently involves the central nervous system and causes various neurological symptoms
liter - a metric unit of capacity equal to the volume of 1 kilogram of pure water at 4 degrees centigrade and 760 mm of mercury (or approximately 1.76 pints)
literacy - the ability to read and write
lithiasis - the formation of stones (calculi) in an internal organ
lithium carbonate - a white powder (LiCO3) used in manufacturing glass and ceramics and as a drug; the drug (trade names Lithane or Lithonate or Eskalith) is used to treat some forms of depression and manic episodes of manic-depressive disorder
lithium - a soft silver-white univalent element of the alkali metal group; the lightest metal known; occurs in several minerals
live birth - the birth of a living fetus (regardless of the length of gestation)
liver - having a reddish-brown color; large and complicated reddish-brown glandular organ located in the upper right portion of the abdominal cavity; secretes bile and functions in metabolism of protein and carbohydrate and fat; synthesizes substances involved in the clotting of the blood; synthesizes vitamin A; detoxifies poisonous substances and breaks down worn-out erythrocytes; liver of an animal used as meat; someone who lives in a place; a person who has a special life style
lobe - a rounded projection that is part of a larger structure; (anatomy) a somewhat rounded subdivision of a bodily organ or part; the enhanced response of an antenna in a given direction as indicated by a loop in its radiation pattern; (botany) a part into which a leaf is divided
lobectomy - surgical removal of a lobe from any organ of the body (as the lung or brain)
lobule - a small lobe or subdivision of a lobe
local anesthesia - loss of sensation in a small area of the body (as when a local anesthetic is injected for a tooth extraction)
local anesthetic - anesthetic that numbs a particular area of the body
local - relating to or applicable to or concerned with the administration of a city or town or district rather than a larger area; affecting only a restricted part or area of the body; of or belonging to or characteristic of a particular locality or neighborhood; public transport consisting of a bus or train that stops at all stations or stops; anesthetic that numbs a particular area of the body
location - a point or extent in space; a workplace away from a studio at which some or all of a movie may be made; a determination of the place where something is; the act of putting something in a certain place
locomotion - self-propelled movement; the power or ability to move
locus - the set of all points or lines that satisfy or are determined by specific conditions; the specific site of a particular gene on its chromosome; the scene of any event or action (especially the place of a meeting)
lomustine - an antineoplastic drug often used to treat brain tumors or Hodgkin's disease
loneliness - the state of being alone in solitary isolation; a disposition toward being alone; sadness resulting from being forsaken or abandoned
lorazepam - tranquilizer (trade name Ativan) used to treat anxiety and tension and insomnia
lotion - any of various cosmetic preparations that are applied to the skin; liquid preparation having a soothing or antiseptic or medicinal action when applied to the skin
louse - wingless usually flattened bloodsucking insect parasitic on warm-blooded animals; wingless insect with mouth parts adapted for biting; mostly parasitic on birds; any of several small insects especially aphids that feed by sucking the juices from plants; a person who has a nasty or unethical character undeserving of respect
lovastatin - an oral drug (trade name Mevacor) to reduce blood cholesterol levels; used when dietary changes have proved inadequate
love - any object of warm affection or devotion; a deep feeling of sexual desire and attraction; a strong positive emotion of regard and affection; a score of zero in tennis or squash; sexual activities (often including sexual intercourse) between two people; a beloved person; used as terms of endearment; verb have a great affection or liking for; be enamored or in love with; get pleasure from; have sexual intercourse with
lubricant - a substance capable of reducing friction by making surfaces smooth or slippery
lumbar puncture - removal by centesis of fluid from the subarachnoid space of the lumbar region of the spinal cord for diagnostic or therapeutic purposes
lung - either of two saclike respiratory organs in the chest of vertebrates; serves to remove carbon dioxide and provide oxygen to the blood
lupus erythematosus - a chronic inflammatory collagen disease affecting connective tissue (skin or joints)
lutein - yellow carotenoid pigments in plants and animal fats and egg yolks
luteinizing hormone - a gonadotropic hormone that is secreted by the anterior pituitary; stimulates ovulation in female mammals and stimulates androgen release in male mammals
lycopene - carotenoid that makes tomatoes red; may lower the risk of prostate cancer
lyme disease - an acute inflammatory disease characterized by a rash with joint swelling and fever; caused by bacteria carried by the bite of a deer tick
lymph node - the source of lymph and lymphocytes
lymph - a thin coagulable fluid (similar to plasma but) containing white blood cells (lymphocytes) and chyle; is conveyed to the blood stream by lymphatic vessels
lymphadenitis - inflammation of lymph nodes
lymphadenopathy - chronic abnormal enlargement of the lymph nodes (usually associated with disease)
lymphangiectasis - dilatation of a lymph vessel
lymphangiography - roentgenographic examination of lymph nodes and lymph vessels after injection of a radiopaque contrast medium; produces a lymphangiogram
lymphangioma - benign angioma consisting of a mass of lymphatic vessels
lymphangitis - inflammation of a lymph vessel
lymphatic system - the interconnected system of spaces and vessels between body tissues and organs by which lymph circulates throughout the body
lymphatic tissue - tissue making up the lymphatic system
lymphatic vessel - a vascular duct that carries lymph which is eventually added to the venous blood circulation
lymphedema - swelling (usually in the legs) caused by lymph accumulating in the tissues
lymphoblast - an immature lymphocyte
lymphocyte - an agranulocytic leukocyte that normally makes up a quarter of the white blood cell count but increases in the presence of infection
lymphocytic leukemia - leukemia characterized by enlargement of lymphoid tissues and lymphocytic cells in the circulating blood
lymphocytosis - an abnormal increase in the number of lymphocytes in the circulating blood
lymphogranuloma venereum - infectious disease caused by a species of chlamydia bacterium; transmitted by sexual contact; characterized by genital lesions and swelling of lymph nodes in the groin
lymphokine - a cytokine secreted by helper T cells in response to stimulation by antigens and that acts on other cells of the immune system (as by activating macrophages)
lymphoma - a neoplasm of lymph tissue that is usually malignant; one of the four major types of cancer
lymphopenia - an abnormally small number of lymphocytes in the circulating blood
lymphopoiesis - the formation of lymphocytes in the bone marrow and lymph nodes and thymus and spleen
lysine - an essential amino acid found in proteins; occurs especially in gelatin and casein
lysogeny - the condition of a host bacterium that has incorporated a phage into its own genetic material
lysosome - an organelle found in the cytoplasm of most cells (especially in leukocytes and liver and kidney cells)
lyssavirus - a neurotropic non-arbovirus of the family Rhabdoviridae that causes rabies
macrocephaly - an abnormally large head; differs from hydrocephalus because there is no increased intracranial pressure and the overgrowth is symmetrical
macrocytic anemia - anemia in which the average size of erythrocytes is larger than normal
macroglossia - a congenital disorder characterized by an abnormally large tongue; often seen in cases of Down's syndrome
macrophage - a large phagocyte; some are fixed and other circulate in the blood stream
macular degeneration - degeneration of the cells of the macula lutea which results in blurred vision and can cause blindness; usually age-related
macule - a patch of skin that is discolored but not usually elevated; caused by various diseases
magnesium hydroxide - a white crystalline powder used chiefly in medicines
magnesium oxide - a white solid mineral that occurs naturally as periclase; a source of magnesium
magnesium sulfate - a salt of magnesium
magnesium - a light silver-white ductile bivalent metallic element; in pure form it burns with brilliant white flame; occurs naturally only in combination (as in magnesite and dolomite and carnallite and spinel and olivine)
magnetic resonance imaging - the use of nuclear magnetic resonance of protons to produce proton density images
maintenance - the unauthorized interference in a legal action by a person having no interest in it (as by helping one party with money or otherwise to continue the action) so as to obstruct justice or promote unnecessary litigation or unsettle the peace of the community; means of maintenance of a family or group; activity involved in maintaining something in good working order; the act of sustaining life by food or providing a means of subsistence; court-ordered support paid by one spouse to another after they are separated
malabsorption syndrome - a pattern of symptoms including loss of appetite and bloating and weight loss and muscle pain and steatorrhea; associated with celiac disease and sprue and cystic fibrosis
malabsorption - abnormal absorption of nutrients from the digestive tract
malaise - physical discomfort (as mild sickness or depression)
malaria - an infective disease caused by sporozoan parasites that are transmitted through the bite of an infected Anopheles mosquito; marked by paroxysms of chills and fever
malathion - a yellow insecticide used as a dust or spray to control garden pests and house flies and mites
male hypogonadism - the state of being a eunuch (either because of lacking testicles or because they failed to develop)
male - being the sex (of plant or animal) that produces gametes (spermatozoa) that perform the fertilizing function in generation; for or pertaining to or composed of men or boys; characteristic of a man; an animal that produces gametes (spermatozoa) that can fertilize female gametes (ova); the capital of Maldives in the center of the islands; a person who belongs to the sex that cannot have babies
malignant hypertension - severe hypertension that runs a rapid course and damages the inner linings of the blood vessels and the heart and spleen and kidneys and brain
malingering - evading duty or work by pretending to be incapacitated
malleus - the ossicle attached to the eardrum
malnutrition - a state of poor nutrition; can result from insufficient or excessive or unbalanced diet or from inability to absorb foods
malocclusion - (dentistry) a condition in which the opposing teeth do not mesh normally
malposition - faulty position
maltose - a white crystalline sugar formed during the digestion of starches
mammary gland - milk-secreting organ of female mammals
mammography - a diagnostic procedure to detect breast tumors by the use of X rays
mandible - the jaw in vertebrates that is hinged to open the mouth
mandibular condyle - the condyle of the ramus of the mandible that articulates with the skull
manganese - a hard brittle grey polyvalent metallic element that resembles iron but is not magnetic; used in making steel; occurs in many minerals
manic disorder - a mood disorder; an affective disorder in which the victim tends to respond excessively and sometimes violently
manic - affected with or marked by frenzy or mania uncontrolled by reason
mannitol - a diuretic (trade name Osmitrol) used to promote the excretion of urine
margaric acid - a colorless crystalline synthetic fatty acid
marijuana - a strong-smelling plant from whose dried leaves a number of euphoriant and hallucinogenic drugs are prepared; the most commonly used illicit drug; considered a soft drug, it consists of the dried leaves of the hemp plant; smoked or chewed for euphoric effect
marked - singled out for notice or especially for a dire fate; strongly marked; easily noticeable; having or as if having an identifying mark or a mark as specified; often used in combination
married - joined in matrimony; of or relating to the state of marriage; a person who is married
mass spectrometer - spectroscope for obtaining a mass spectrum by deflecting ions into a thin slit and measuring the ion current with an electrometer
mast cell - a large connective tissue cell that contains histamine and heparin and serotonin which are released in allergic reactions or in response to injury or inflammation
mastectomy - surgical removal of a breast to remove a malignant tumor
masticate - verb grind and knead; chew (food)
mastitis - inflammation of a breast (or udder)
mastoidectomy - surgical removal of some or all of the mastoid process
mastoiditis - inflammation of the mastoid
mastopexy - plastic surgery to lift or reshape the breasts
masturbation - manual stimulation of the genital organs (of yourself or another) for sexual pleasure
material - derived from or composed of matter; directly relevant to a matter especially a law case; concerned with or affecting physical as distinct from intellectual or psychological well-being; concerned with worldly rather than spiritual interests; having substance or capable of being treated as fact; not imaginary; having material or physical form or substance; things needed for doing or making something; information (data or ideas or observations) that can be used or reworked into a finished form; a person judged suitable for admission or employment; the tangible substance that goes into the makeup of a physical object; artifact made by weaving or felting or knitting or crocheting natural or synthetic fibers
mathematics - a science (or group of related sciences) dealing with the logic of quantity and shape and arrangement
mating - the act of pairing a male and female for reproductive purposes
maxilla - the jaw in vertebrates that is fused to the cranium
maxillary sinus - one of a pair of sinuses forming a cavity in the maxilla
maximum - the greatest or most complete or best possible; the point on a curve where the tangent changes from positive on the left to negative on the right; the largest possible quantity; the greatest possible degree
mean - (used of persons or behavior) characterized by or indicative of lack of generosity; excellent; of no value or worth; (used of sums of money) so small in amount as to deserve contempt; characterized by malice; having or showing an ignoble lack of honor or morality; approximating the statistical norm or average or expected value; marked by poverty befitting a beggar; an average of n numbers computed by adding some function of the numbers and dividing by some function of n; verb destine or designate for a certain purpose; denote or connote; mean or intend to express or convey; have a specified degree of importance; have in mind as a purpose; intend to refer to; have as a logical consequence
measles - an acute and highly contagious viral disease marked by distinct red spots followed by a rash; occurs primarily in children
measurement - the act or process of assigning numbers to phenomena according to a rule
mebendazole - an anthelmintic used to treat hookworm and pinworm and roundworm infestations
meclizine - an antihistamine (trade name Antivert) used to treat or prevent motion sickness
medial - dividing an animal into right and left halves; relating to or situated in or extending toward the middle
median - relating to or situated in or extending toward the middle; relating to or constituting the middle value of an ordered set of values (or the average of the middle two in a set with an even number of values); dividing an animal into right and left halves; the value below which 50% of the cases fall
mediastinum - the part of the thoracic cavity between the lungs that contains the heart and aorta and esophagus and trachea and thymus
medicaid - health care for the needy; a federally and state-funded program
medical history - the case history of a medical patient as recalled by the patient
medical record - the case history of a medical patient as recalled by the patient
medicare - health care for the aged; a federally administered system of health insurance available to persons aged 65 and over
medicine - the learned profession that is mastered by graduate training in a medical school and that is devoted to preventing or alleviating or curing diseases and injuries; (medicine) something that treats or prevents or alleviates the symptoms of disease; the branches of medical science that deal with nonsurgical techniques; punishment for one's actions; verb treat medicinally, treat with medicine
meditation - continuous and profound contemplation or musing on a subject or series of subjects of a deep or abstruse nature; (religion) contemplation of spiritual matters (usually on religious or philosophical subjects)
medroxyprogesterone - a progestin compound (trade name Provera) used to treat menstrual disorders
medulla oblongata - lower or hindmost part of the brain; continuous with spinal cord; (`bulb' is an old term for medulla oblongata)
mefenamic acid - a nonsteroidal anti-inflammatory and analgesic drug (trade name Ponstel) used to treat mild pain (especially menstrual cramps)
mefloquine - an antimalarial drug (trade name Larium and Mephaquine) that is effective in cases that do not respond to chloroquine; said to produce harmful neuropsychiatric effects on some people
megacolon - an abnormal enlargement of the colon; can be congenital (as in Hirschsprung's disease) or acquired (as when children refuse to defecate)
megakaryocyte - a large bone marrow cell; regarded as the source of blood platelets
megaloblastic anemia - anemia characterized by many large immature and dysfunctional red blood cells (megaloblasts) in the bone marrow; associated with pernicious anemia
megestrol acetate - a synthetic progestational compound used to treat endometrial carcinoma
meiosis - (genetics) cell division that produces reproductive cells in sexually reproducing organisms; the nucleus divides into four nuclei each containing half the chromosome number (leading to gametes in animals and spores in plants); understatement for rhetorical effect (especially when expressing an affirmative by negating its contrary)
melancholia - extreme depression characterized by tearful sadness and irrational fears
melanin - insoluble pigments that account for the color of e.g. skin and scales and feathers
melanocyte - a cell in the basal layer of the epidermis that produces melanin under the control of the melanocyte-stimulating hormone
melanoma - any of several malignant neoplasms (usually of the skin) consisting of melanocytes
melatonin - hormone secreted by the pineal gland
melena - abnormally dark tarry feces containing blood (usually from gastrointestinal bleeding)
melphalan - antineoplastic drug (trade name Alkeran) used to treat multiple myeloma and some other malignancies
membrane - a thin pliable sheet of material; a pliable sheet of tissue that covers or lines or connects organs or cells of animals
memory - an electronic memory device; the power of retaining and recalling past experience; the cognitive processes whereby past experience is remembered; something that is remembered; the area of cognitive psychology that studies memory processes
menarche - the first occurrence of menstruation in a woman
meniere's disease - a disease of the inner ear characterized by episodes of dizziness and tinnitus and progressive hearing loss (usually unilateral)
meninges - a membrane (one of 3) that envelops the brain and spinal cord
meningioma - a tumor arising in the meninges which surround the brain and spinal cord; usually slow growing and sometimes malignant
meningism - symptoms that mimic those of meningitis but without inflammation of the meninges
meningitis - infectious disease characterized by inflammation of the meninges (the tissues that surround the brain or spinal cord) usually caused by a bacterial infection; symptoms include headache and stiff neck and fever and nausea
meningocele - a congenital anomaly of the central nervous system in which a sac protruding from the brain or the spinal meninges contains cerebrospinal fluid (but no nerve tissue)
meningoencephalitis - inflammation of the brain and spinal cord and their meninges
menopause - the time in a woman's life in which the menstrual cycle ends
menorrhagia - abnormally heavy or prolonged menstruation; can be a symptom of uterine tumors and can lead to anemia if prolonged
menstrual cycle - a recurring cycle (beginning at menarche and ending at menopause) in which the endometrial lining of the uterus prepares for pregnancy; if pregnancy does not occur the lining is shed at menstruation
menstruation - the monthly discharge of blood from the uterus of nonpregnant women from puberty to menopause
mental health - the psychological state of someone who is functioning at a satisfactory level of emotional and behavioral adjustment
mental process - (psychology) the performance of some composite cognitive activity; an operation that affects mental contents
mental retardation - lack of normal development of intellectual capacities
menthol - a lotion containing menthol which gives it the smell of mint; a crystalline compound that has the cool and minty taste and odor that occurs naturally in peppermint oil; used as a flavoring and in medicine to relieve itching, pain, and nasal congestion
meperidine hydrochloride - a synthetic narcotic drug (trade name Demerol) used to treat pain
meperidine - a synthetic narcotic drug (trade name Demerol) used to treat pain
mephenytoin - a toxic anticonvulsant drug (trade name Mesantoin) used in the treatment of epilepsy when less toxic anticonvulsants have been ineffective
meprobamate - a sedative and tranquilizer (trade name Miltown and Equanil and Meprin) used to treat muscle tension and anxiety
mercaptopurine - a drug (trade name Purinethol) that interferes with the metabolism of purine and is used to treat acute lymphocytic leukemia
mercury poisoning - a toxic condition caused by ingesting or inhaling mercury; acute mercury poisoning causes a metallic taste and vomiting and diarrhea and kidney problems that may lead to death
mercury - temperature measured by a mercury thermometer; the smallest planet and the nearest to the sun; (Roman mythology) messenger of Jupiter and god of commerce; counterpart of Greek Hermes; a heavy silvery toxic univalent and bivalent metallic element; the only metal that is liquid at ordinary temperatures
meridian - of or happening at noon; being at the best stage of development; an imaginary great circle on the surface of the earth passing through the north and south poles at right angles to the equator; a town in eastern Mississippi; the highest level or degree attainable; the highest stage of development
mesencephalon - the middle portion of the brain
mesenchyme - mesodermal tissue that forms connective tissue and blood and smooth muscles
mesenteric artery - one of two branches of the aorta that pass between the two layers of the mesentery to the intestines
mesentery - a double layer of peritoneum that attaches to the back wall of the abdominal cavity and supports the small intestines
mesoderm - the middle germ layer that develops into muscle and bone and cartilage and blood and connective tissue
mesothelioma - a rare form of carcinoma of the mesothelium lining lungs or abdomen or heart; usually associated with exposure to asbestos dust
mesothelium - epithelium originating in the embryonic mesoderm; lines the primordial body cavity
messenger rna - the template for protein synthesis; the form of RNA that carries information from DNA in the nucleus to the ribosome sites of protein synthesis in the cell
mestranol - a synthetic form of estrogen used in combination with a progestin in oral contraceptives
metabolic acidosis - acidosis and bicarbonate concentration in the body fluids resulting either from the accumulation of acids or the abnormal loss of bases from the body (as in diarrhea or renal disease)
metabolism - the organic processes (in a cell or organism) that are necessary for life; the marked and rapid transformation of a larva into an adult that occurs in some animals
metabolite - any substance involved in metabolism (either as a product of metabolism or as necessary for metabolism)
metacarpal bone - any bone of the hand between the wrist and fingers
metadata - data about data
metal - containing or made of or resembling or characteristic of a metal; a mixture containing two or more metallic elements or metallic and nonmetallic elements usually fused together or dissolving into each other when molten; any of several chemical elements that are usually shiny solids that conduct heat or electricity and can be formed into sheets etc.; verb cover with metal
metamorphosis - a complete change of physical form or substance especially as by magic or witchcraft; the marked and rapid transformation of a larva into an adult that occurs in some animals; a striking change in appearance or character or circumstances
metaphase - the second stage of mitosis; the second stage of meiosis
metaphysis - the growing part of a long bone between the diaphysis and the epiphysis
metastasis - the spreading of a disease to another part of the body; the organic processes (in a cell or organism) that are necessary for life
metastatic - relating to or affected by metastasis
metencephalon - the part of the hindbrain that develops into the pons and the cerebellum
meter - any of various measuring instruments for measuring a quantity; rhythm as given by division into parts of equal duration; (prosody) the accent in a metrical foot of verse; the basic unit of length adopted under the Systeme International d'Unites (approximately 1.094 yards); verb measure with a meter; stamp with a meter indicating the postage
metformin - an antidiabetic drug (trade name Glucophage) prescribed to treat type II diabetes
methadone hydrochloride - synthetic narcotic drug similar to morphine but less habit-forming; used in narcotic detoxification and maintenance of heroin addiction
methadone - synthetic narcotic drug similar to morphine but less habit-forming; used in narcotic detoxification and maintenance of heroin addiction
methamphetamine - an amphetamine derivative (trade name Methedrine) used in the form of a crystalline hydrochloride; used as a stimulant to the nervous system and as an appetite suppressant
methane - a colorless odorless gas used as a fuel
methanol - a light volatile flammable poisonous liquid alcohol; used as an antifreeze and solvent and fuel and as a denaturant for ethyl alcohol
methaqualone - sedative-hypnotic drug (trade name Quaalude) that is a drug of abuse
methenamine - antibacterial agent (trade names Mandelamine and Urex) that is contained in many products that are used to treat urinary infections
methicillin - antibiotic drug of the penicillin family used in the treatment of certain staphylococcal infections
methionine - a crystalline amino acid containing sulfur; found in most proteins and essential for nutrition
methocarbamol - muscle relaxant for skeletal muscles (trade name Robaxin) used to treat spasms
methodology - the system of methods followed in a particular discipline; the branch of philosophy that analyzes the principles and procedures of inquiry in a particular discipline
methotrexate - toxic antimetabolite that limits cellular reproduction by acting as an antagonist to folic acid; used to treat certain cancers and psoriasis and rheumatoid arthritis
methyldopa - antihypertensive drug (trade name Aldomet) used in the treatment of high blood pressure
methylene blue - a dark green dye used as a stain, an antiseptic, a chemical indicator, and an antidote in cyanide poisoning
methylene chloride - a nonflammable liquid used as a solvent and paint remover and refrigerant
methylphenidate - central nervous system stimulant (trade name Ritalin) used in the treatment of narcolepsy in adults and attention deficit disorder in children
methyltestosterone - an androgenic compound contained in drugs that are used to treat testosterone deficiency and female breast cancer and to stimulate growth and weight gain
metoprolol - beta blocker (trade name Lopressor) used in treating hypertension and angina and arrhythmia and acute myocardial infarction; has adverse side effects (depression and exacerbation of congestive heart failure etc.)
metric system - a decimal system of weights and measures based on the meter and the kilogram and the second
metronidazole - antiprotozoal medication (trade name Flagyl) used to treat trichomoniasis and giardiasis
metrorrhagia - bleeding from the uterus that is not due to menstruation; usually indicative of disease (as cervical cancer)
mexiletine - antiarrhythmic drug (trade name Mexitil) used to treat ventricular arrhythmias
micelle - an electrically charged particle built up from polymeric molecules or ions and occurring in certain colloidal electrolytic solutions like soaps and detergents
miconazole - an antifungal agent usually administered in the form of a nitrate (trade name Monistat)
microbiology - the branch of biology that studies microorganisms and their effects on humans
micrococcaceae - spherical or elliptical usually aerobic eubacteria that produce yellow or orange or red pigment; includes toxin-producing forms as well as harmless commensals and saprophytes
micrococcus - type genus of the family Micrococcaceae
microglia - neuroglial tissue of mesodermal origin that can become phagocytic
microgram - one millionth (1/1,000,000) gram
micronutrient - a substance needed only in small amounts for normal body function (e.g., vitamins or minerals)
microorganism - any organism of microscopic size
microscopic - too small to be seen except under a microscope; extremely precise with great attention to details; of or relating to or used in microscopy; infinitely or immeasurably small
microscopy - research with the use of microscopes
microsome - a tiny granule in the cytoplasm that is where protein synthesis takes place under the direction of mRNA
microsporum - a genus of fungus of the family Moniliaceae; causes ringworm
microsurgery - surgery using operating microscopes and miniaturized precision instruments to perform intricate procedures on very small structures
microtubule - a microscopically small tubule
microvolt - a unit of potential equal to one millionth of a volt
midazolam - an injectable form of benzodiazepine (trade name Versed) useful for sedation and for reducing pain during uncomfortable medical procedures
middle ear - the main cavity of the ear; between the eardrum and the inner ear
mifepristone - an abortion-inducing drug (trade name RU_486) developed in France; when taken during the first five weeks of pregnancy it blocks the action of progesterone so that the uterus sloughs off the embryo
migraine - a severe recurring vascular headache; occurs more frequently in women than men
mild - moderate in type or degree or effect or force; far from extreme; mild and pleasant; humble in spirit or manner; suggesting retiring mildness or even cowed submissiveness
mile - a footrace extending one mile; a unit of length equal to 1760 yards; a Swedish unit of length equivalent to 10 km; an ancient Roman unit of length equivalent to 1620 yards; a large distance; a unit of length used in navigation; equivalent to the distance spanned by one minute of arc in latitude; 1,852 meters; a British unit of length equivalent to 1,853.18 meters (6,082 feet); a former British unit of length once used in navigation; equivalent to 1828.8 meters (6000 feet)
miliaria - obstruction of the sweat ducts during high heat and humidity
military personnel - soldiers collectively; someone who serves in the armed forces; a member of a military force
milk - produced by mammary glands of female mammals for feeding their young; a white nutritious liquid secreted by mammals and used as food by human beings; any of several nutritive milklike liquids; a river that rises in the Rockies in northwestern Montana and flows eastward to become a tributary of the Missouri River; verb take milk from female mammals; add milk to; exploit as much as possible
millicurie - a unit of radioactivity equal to one thousandth of a curie
milligram - one thousandth (1/1,000) gram
milliliter - a metric unit of volume equal to one thousandth of a liter
millimeter - a metric unit of length equal to one thousandth of a meter
millivolt - a unit of potential equal to one thousandth of a volt
mindfulness - the trait of staying aware of (paying close attention to) your responsibilities
mineral oil - a distillate of petroleum (especially one used medicinally as a laxative or stool softener)
mineral - of or containing or derived from minerals; composed of matter other than plant or animal; relating to minerals; solid homogeneous inorganic substances occurring in nature having a definite chemical composition
mineralocorticoid - hormone that is one of the steroids of the adrenal cortex that influences the metabolism of sodium and potassium
minoxidil - a vasodilator (trade name Loniten) used to treat severe hypertension; one side effect is hirsutism so it is also sold (trade name Rogaine) as a treatment for male-patterned baldness
miotic - of or relating to or causing constriction of the pupil of the eye; a drug that causes miosis (constriction of the pupil of the eye)
misalignment - the spatial property of things that are not properly aligned
mite - any of numerous very small to minute arachnids often infesting animals or plants or stored foods; a slight but appreciable addition
mithramycin - an antineoplastic drug (trade name Mithracin) used to treat cancer of the testes
mitochondrion - an organelle containing enzymes responsible for producing energy
mitogen - an agent that triggers mitosis
mitomycin - a complex of antibiotic substances obtained from a streptomyces bacterium; one form (trade name Mutamycin) shows promise as an anticancer drug
mitosis - cell division in which the nucleus divides into nuclei containing the same number of chromosomes
mitral valve prolapse - cardiopathy resulting from the mitral valve not regulating the flow of blood between the left atrium and left ventricle of the heart
mitral valve stenosis - obstruction or narrowing of the mitral valve (as by scarring from rheumatic fever)
mitral valve - valve with two cusps; situated between the left atrium and the left ventricle
mittelschmerz - pain in the area of the ovary that is felt at the time of ovulation (usually midway through the menstrual cycle)
modality - a method of therapy that involves physical or electrical therapeutic treatment; a particular sense; a classification of propositions on the basis of whether they claim necessity or possibility or impossibility; verb inflections that express how the action or state is conceived by the speaker
molar - pertaining to large units of behavior; containing one mole of a substance; designating a solution containing one mole of solute per liter of solution; of or pertaining to the grinding teeth in the back of a mammal's mouth; grinding tooth with a broad crown; located behind the premolars
molecular biology - the branch of biology that studies the structure and activity of macromolecules essential to life (and especially with their genetic role)
molecular weight - (chemistry) the sum of the relative atomic masses of the constituent atoms of a molecule
molecule - (physics and chemistry) the simplest structural unit of an element or compound; (nontechnical usage) a tiny piece of anything
mollusca - gastropods; bivalves; cephalopods; chitons
molt - periodic shedding of the cuticle in arthropods or the outer skin in reptiles; verb cast off hair, skin, horn, or feathers
molybdenum - a polyvalent metallic element that resembles chromium and tungsten in its properties; used to strengthen and harden steel
monitoring device - display produced by a device that takes signals and displays them on a television screen or a computer monitor
monoclonal antibody - any of a class of antibodies produced in the laboratory by identical offspring of a hybridoma; very specific for a particular location in the body
monocyte - a type of granular leukocyte that functions in the ingestion of bacteria
monocytosis - increase in the number of monocytes in the blood; symptom of monocytic leukemia
monograph - a detailed and documented treatise on a particular subject
monomer - a simple compound whose molecules can join together to form polymers
mononucleosis - an acute disease characterized by fever and swollen lymph nodes and an abnormal increase of mononuclear leucocytes or monocytes in the bloodstream; not highly contagious; some believe it can be transmitted by kissing
monosaccharide - a sugar (like sucrose or fructose) that does not hydrolyse to give other sugars; the simplest group of carbohydrates
monosomy - chromosomal abnormality consisting of the absence of one chromosome from the normal diploid number
monozygotic twin - either of two twins developed from the same fertilized ovum (having the same genetic material)
moral - concerned with principles of right and wrong or conforming to standards of behavior and character based on those principles; psychological rather than physical or tangible in effect; arising from the sense of right and wrong; relating to principles of right and wrong; i.e. to morals or ethics; adhering to ethical and moral principles; the significance of a story or event
morale - a state of individual psychological well-being based upon a sense of confidence and usefulness and purpose; the spirit of a group that makes the members want the group to succeed
morning sickness - nausea early in the day; a characteristic symptom in the early months of pregnancy
moro reflex - a normal reflex of young infants; a sudden loud noise causes the child to stretch out the arms and flex the legs
morphine - an alkaloid narcotic drug extracted from opium; a powerful, habit-forming narcotic used to relieve pain
morphogenesis - differentiation and growth of the structure of an organism (or a part of an organism)
mortality - the quality or state of being mortal; the ratio of deaths in an area to the population of that area; expressed per 1000 per year
morula - a solid mass of blastomeres that forms when the zygote splits; develops into the blastula
motion sickness - the state of being dizzy or nauseated because of the motions that occur while traveling in or on a moving vehicle
motivation - the psychological feature that arouses an organism to action toward a desired goal; the reason for the action; that which gives purpose and direction to behavior; the act of motivating; providing incentive; the condition of being motivated
motor cortex - the cortical area that influences motor movements
motor neuron - a neuron conducting impulses outwards from the brain or spinal cord
motorized wheelchair - a wheelchair propelled by a motor
mouthwash - a medicated solution used for gargling and rinsing the mouth
mucin - a nitrogenous substance found in mucous secretions; a lubricant that protects body surfaces
mucinous - relating to or containing mucin
mucopolysaccharide - complex polysaccharides containing an amino group; occur chiefly as components of connective tissue
mucopolysaccharidosis - any of a group of genetic disorders involving a defect in the metabolism of mucopolysaccharides resulting in greater than normal levels of mucopolysaccharides in tissues
mucor - any mold of the genus Mucor
mucorales - an order of mostly saprophytic fungi
mucous membrane - mucus-secreting membrane lining all body cavities or passages that communicate with the exterior
mucus - protective secretion of the mucous membranes; in the gut it lubricates the passage of food and protects the epithelial cells; in the nose and throat and lungs it can make it difficult for bacteria to penetrate the body through the epithelium
multiple myeloma - myeloma that develops in several places at the same time
multiple sclerosis - a chronic progressive nervous disorder involving loss of myelin sheath around certain nerve fibers
multiplicity - the property of being multiple; a large number
mumps - an acute contagious viral disease characterized by fever and by swelling of the parotid glands
muramidase - an enzyme found in saliva and sweat and tears that destroys the cell walls of certain bacteria
muscidae - two-winged flies especially the housefly
muscle cell - an elongated contractile cell that forms the muscles of the body
muscle contraction - (physiology) a shortening or tensing of a part or organ (especially of a muscle or muscle fiber)
muscle fiber - an elongated contractile cell that forms the muscles of the body
muscle relaxant - a drug that reduces muscle contractility by blocking the transmission of nerve impulses or by decreasing the excitability of the motor end plate or by other actions
muscle - authority or power or force (especially when used in a coercive way); animal tissue consisting predominantly of contractile cells; one of the contractile organs of the body; possessing muscular strength; a bully employed as a thug or bodyguard; verb make one's way by force
muscular dystrophy - any of several hereditary diseases of the muscular system characterized by weakness and wasting of skeletal muscles
musculoskeletal system - the system of muscles and tendons and ligaments and bones and joints and associated tissues that move the body and maintain its form
musculoskeletal - relating to muscles and skeleton
mustard gas - a toxic war gas with sulfide based compounds that raises blisters and attacks the eyes and lungs; there is no known antidote
mutant - tending to undergo or resulting from mutation; an animal that has undergone mutation; (biology) an organism that has characteristics resulting from chromosomal alteration
mutate - verb undergo mutation
mutation - a change or alteration in form or qualities; (genetics) any event that changes genetic structure; any alteration in the inherited nucleic acid sequence of the genotype of an organism; (biology) an organism that has characteristics resulting from chromosomal alteration
mutism - the condition of being unable or unwilling to speak
myalgia - pain in a muscle or group of muscles
myasthenia - any muscular weakness; a chronic progressive disease characterized by chronic fatigue and muscular weakness (especially in the face and neck); caused by a deficiency of acetylcholine at the neuromuscular junctions
mycelium - the vegetative part of a fungus consisting of a mass of branching threadlike hyphae
mycobacteriaceae - a family of bacteria
mycobacterium leprae - cause of leprosy
mycobacterium tuberculosis - cause of tuberculosis
mycobacterium - rod-shaped bacteria some saprophytic or causing diseases
mycoplasma - any of a group of small parasitic bacteria that lack a cell walls and can survive without oxygen; can cause pneumonia and urinary tract infection
mycoplasmal pneumonia - an acute respiratory disease marked by high fever and coughing; caused by mycoplasma; primarily affecting children and young adults
mycoplasmataceae - pleomorphic Gram-negative nonmotile microorganism similar to both viruses and bacteria; parasitic in mammals
mycosis - an inflammatory condition caused by a fungus
mycotoxin - a toxin produced by a fungus
mydriasis - reflex pupillary dilation as a muscle pulls the iris outward; occurs in response to a decrease in light or certain drugs
myelin sheath - a layer of myelin encasing (and insulating) the axons of medullated nerve fibers
myelin - a white fatty substance that forms a medullary sheath around the axis cylinder of some nerve fibers
myelitis - inflammation of the spinal cord
myeloblast - a precursor of leukocytes that normally occurs only in bone marrow
myelocyte - an immature leukocyte normally found in bone marrow
myelofibrosis - fibrosis of the bone marrow
myelography - roentgenography of the spinal cord to detect possible lesions (usually after injection of a contrast medium into the subarachnoid space)
myeloid - of or relating to bone marrow; of or relating to the spinal cord
myenteric plexus - a plexus of unmyelinated fibers and postganglionic autonomic cell bodies in the muscular coat of the esophagus and stomach and intestines
myiasis - infestation of the body by the larvae of flies (usually through a wound or other opening) or any disease resulting from such infestation
myocardial infarction - destruction of heart tissue resulting from obstruction of the blood supply to the heart muscle
myocarditis - inflammation of the myocardium (the muscular tissue of the heart)
myocardium - the middle muscular layer of the heart wall
myoclonus - a clonic spasm of a muscle or muscle group
myofibril - one of many contractile filaments that make up a striated muscle fiber
myoglobin - a hemoprotein that receives oxygen from hemoglobin and stores it in the tissues until needed
myoglobinuria - the presence of myoglobin in the urine
myoma - a benign tumor composed of muscle tissue
myometrium - the smooth muscle forming the wall of the uterus
myopathy - any pathology of the muscles that is not attributable to nerve dysfunction
myopia - (ophthalmology) eyesight abnormality resulting from the eye's faulty refractive ability; distant objects appear blurred
myositis - inflammation of muscle tissue
myotonia congenita - a mild, rare, congenital form of myotonia characterized by muscle stiffness
myotonia - abnormally long muscular contractions; slow relaxation of a muscle after a contraction
myotonic dystrophy - a severe form of muscular dystrophy marked by generalized weakness and muscular wasting that affects the face and feet and hands and neck; difficult speech and difficulty with the hands that spreads to the arms and shoulders and legs and hips; the onset can be any time from birth to middle age and the progression is slow; inheritance is autosomal dominant
myristic acid - a saturated fatty acid occurring naturally in animal and vegetable fats
myxedema - hypothyroidism marked by dry skin and swellings around lips and nose as well as mental deterioration
myxoma - a benign tumor of connective tissue containing jellylike material
myxomycete - a slime mold of the class Myxomycetes
nadolol - a beta-adrenergic blocking agent (trade name Corgard) that is used to treat hypertension and angina
nafcillin - a penicillinase-resistant form of penicillin (trade name Nafcil) used (usually in the form of its sodium salt) to treat infections caused by penicillin-resistant strains of staphylococci
nail-biting - (of a situation) characterized by or causing suspense
nalidixic acid - antibacterial agent used especially to treat genitourinary infections
naloxone - a potent narcotic antagonist (trade name Narcan) especially effective with morphine
naltrexone - an oral antagonist against the action of opiates
nandrolone - an androgen (trade names Durabolin or Kabolin) that is used to treat testosterone deficiency or breast cancer or osteoporosis
nanogram - one billionth (1/1,000,000,000) gram
nanometer - a metric unit of length equal to one billionth of a meter
nanosecond - one billionth (10^-9) of a second; one thousandth of a microsecond
nanotechnology - the branch of engineering that deals with things smaller than 100 nanometers (especially with the manipulation of individual molecules)
naphazoline - vasoconstrictor (trade names Privine and Sudafed) used in nasal sprays to treat symptoms of nasal congestion and in eyedrops to treat eye irritation
naphthalene - a white crystalline strong-smelling hydrocarbon made from coal tar or petroleum and used in organic synthesis and as a fumigant in mothballs
naphthoquinone - a fat-soluble vitamin that helps in the clotting of blood
naproxen - a nonsteroidal anti-inflammatory drug (trade name Naprosyn) used in the treatment of arthritis and musculoskeletal inflammation and moderate pain
narcissism - an exceptional interest in and admiration for yourself
narcolepsy - a sleep disorder characterized by sudden and uncontrollable episodes of deep sleep
narcotic antagonist - an antagonist used to counteract the effects of narcotics (especially to counteract the depression of respiration)
narcotic - inducing mental lethargy; inducing stupor or narcosis; of or relating to or designating narcotics; a drug that produces numbness or stupor; often taken for pleasure or to reduce pain; extensive use can lead to addiction
narrow - limited in size or scope; not wide; very limited in degree; lacking tolerance or flexibility or breadth of view; characterized by painstaking care and detailed examination; a narrow strait connecting two bodies of water; verb make or become more narrow or restricted; become tight or as if tight; become more special; define clearly
nasal cavity - either of the two cavities lying between the floor of the cranium and the roof of the mouth and extending from the face to the pharynx
nasal decongestant - a decongestant that provides temporary relief of nasal symptoms of the common cold and rhinitis and upper respiratory infections
nasal septum - a partition of bone and cartilage between the nasal cavities
nasal sinus - any of the paired sinuses in the bones of the face adjacent to the nasal cavity that are lined with mucous membrane that is continuous with the lining of the nasal cavities
nasolacrimal duct - a duct that carries tears from the lacrimal sac to the nasal cavity
nasopharynx - cavity forming the upper part of the pharynx
natural history - the scientific study of plants or animals (more observational than experimental) usually published in popular magazines rather than in academic journals
naturopathy - a method of treating disease using food and exercise and heat to assist the natural healing process
nausea - disgust so strong it makes you feel sick; the state that precedes vomiting
nebulizer - a dispenser that turns a liquid (such as perfume) into a fine mist
neck - an opening in a garment for the neck of the wearer; a part of the garment near the wearer's neck; the part of an organism that connects the head to the rest of the body; a cut of meat from the neck of an animal; a narrow elongated projecting strip of land; verb kiss, embrace, or fondle with sexual passion
necrobiosis lipoidica - skin disease marked by thin shiny patches (especially on the legs); often associated with diabetes mellitus
necrosis - the localized death of living cells (as from infection or the interruption of blood supply)
needle - a sharp pointed implement (usually steel); a slender pointer for indicating the reading on the scale of a measuring instrument; a stylus that formerly made sound by following a groove in a phonograph record; as the leaf of a conifer; verb goad or provoke,as by constant criticism; prick with a needle
negativism - characterized by habitual skepticism and a disagreeable tendency to deny or oppose or resist suggestions or commands
neisseria gonorrhoeae - the pus-producing bacterium that causes gonorrhea
nelfinavir - a protease inhibitor (trade name Viracept) used in treating HIV usually in combination with other drugs
nematoda - unsegmented worms: roundworms; threadworms; eelworms
neocortex - the cortical part of the neencephalon
neomycin - an antibiotic obtained from an actinomycete and used (as a sulphate under the trade name Neobiotic) as an intestinal antiseptic in surgery
neonatal death - death of a liveborn infant within the first 28 days of life
neonatal hyperbilirubinemia - a common disorder that is usually due to immaturity of the liver; usually subsides spontaneously
neonatology - that branch of pediatric medicine concerned with the newborn; the diagnosis and treatment of neonates
neoplastic cell - a cell that is part of tumor
neostigmine - a cholinergic drug (trade name Prostigmin) used to treat some ophthalmic conditions and to treat myasthenia gravis
nephrectomy - surgical removal of a kidney
nephritis - an inflammation of the kidney
nephroblastoma - malignant renal tumor of young children characterized by hypertension and blood in the urine and the presence of a palpable mass
nephrocalcinosis - renal lithiasis in which calcium deposits form in the renal parenchyma and result in reduced kidney function and blood in the urine
nephrolithiasis - the presence of kidney stones (calculi) in the kidney
nephron - any of the small tubules that are the excretory units of the vertebrate kidney
nephrosclerosis - kidney disease that is usually associated with hypertension; sclerosis of the renal arterioles reduces blood flow that can lead to kidney failure and heart failure
nephrosis - a disease affecting the kidneys; a syndrome characterized by edema and large amounts of protein in the urine and usually increased blood cholesterol; usually associated with glomerulonephritis or with a complication of various systemic diseases
nephrotic syndrome - a syndrome characterized by edema and large amounts of protein in the urine and usually increased blood cholesterol; usually associated with glomerulonephritis or with a complication of various systemic diseases
nerve ending - the terminal structure of an axon that does not end at a synapse
nerve fiber - a threadlike extension of a nerve cell
nerve plexus - a network of intersecting nerves
nerve - any bundle of nerve fibers running to various organs and tissues of the body; impudent aggressiveness; the courage to carry on; verb get ready for something difficult or unpleasant
nervous system - the sensory and control apparatus consisting of a network of nerve cells
neural tube - a tube of ectodermal tissue in the embryo from which the brain and spinal cord develop
neuralgia - acute spasmodic pain along the course of one or more nerves
neurasthenia - nervous breakdown (not in technical use)
neurilemma - thin membranous sheath around a nerve fiber
neuritis - inflammation of a nerve accompanied by pain and sometimes loss of function
neuroanatomy - the anatomy of the nervous system
neurobiology - the branch of biology that deals with the anatomy and physiology and pathology of the nervous system
neuroblastoma - malignant tumor containing embryonic nerve cells; usually metastasizes quickly
neurodermatitis - dermatitis in which localized areas (especially the forearms or back of the neck or outer part of the ankle) itch persistently; cause is unknown
neurofibroma - tumor of the fibrous covering of a peripheral nerve
neurofibromatosis - autosomal dominant disease characterized by numerous neurofibromas and by spots on the skin and often by developmental abnormalities
neurofibromatosis - autosomal dominant disease characterized by numerous neurofibromas and by spots on the skin and often by developmental abnormalities
neurogenesis - the development of nerve tissues
neuroglia - sustentacular tissue that surrounds and supports neurons in the central nervous system; glial and neural cells together compose the tissue of the central nervous system
neurohormone - a hormone that is released by nerve impulses (e.g., norepinephrine or vasopressin)
neurologist - a medical specialist in the nervous system and the disorders affecting it
neurology - (neurology) the branch of medicine that deals with the nervous system and its disorders; the branch of medical science that deals with the nervous system
neuroma - any tumor derived from cells of the nervous system
neuromuscular junction - the junction between a nerve fiber and the muscle it supplies
neuron - a cell that is specialized to conduct nerve impulses
neuropathy - any pathology of the peripheral nerves
neuropsychology - the branch of psychology that is concerned with the physiological bases of psychological processes
neurosis - a mental or personality disturbance not attributable to any known neurological or organic dysfunction
neurospora - genus of fungi with black perithecia used extensively in genetic research; includes some forms with orange spore masses that cause severe damage in bakeries
neurosurgeon - someone who does surgery on the nervous system (especially the brain)
neurosurgery - any surgery that involves the nervous system (brain or spinal cord or peripheral nerves)
neurosyphilis - syphilis of the central nervous system
neurotoxin - any toxin that affects neural tissues
neurotransmitter - transmits nerve impulses across a synapse
neurotropism - an affinity for neural tissues
neutron - an elementary particle with 0 charge and mass about equal to a proton; enters into the structure of the atomic nucleus
neutropenia - leukopenia in which the decrease is primarily in number of neutrophils (the chief phagocytic leukocyte)
neutrophil - the chief phagocytic leukocyte; stains with either basic or acid dyes
nevirapine - a non-nucleoside reverse transcriptase inhibitor (trade name Viramune) used to treat AIDS and HIV
nevus - a blemish on the skin that is formed before birth
newborn - having just or recently arisen or come into existence; recently borne; a baby from birth to four weeks
newcastle disease - disease of domestic fowl and other birds
newton - English mathematician and physicist; remembered for developing the calculus and for his law of gravitation and his three laws of motion (1642-1727); a unit of force equal to the force that imparts an acceleration of 1 m/sec/sec to a mass of 1 kilogram; equal to 100,000 dynes
niacin - a B vitamin essential for the normal function of the nervous system and the gastrointestinal tract
nickel - a United States coin worth one twentieth of a dollar; five dollars worth of a drug; a hard malleable ductile silvery metallic element that is resistant to corrosion; used in alloys; occurs in pentlandite and smaltite and garnierite and millerite; verb plate with nickel
nicotine - an alkaloid poison that occurs in tobacco; used in medicine and as an insecticide
nictitating membrane - a protective fold of skin in the eyes of reptiles and birds and some mammals
nifedipine - calcium blocker (trade name Procardia); appears to increase the risk of recurrent heart attacks
night blindness - inability to see clearly in dim light; due to a deficiency of vitamin A or to a retinal disorder
nightmare - a terrifying or deeply upsetting dream; a situation resembling a terrifying dream
nitric acid - acid used especially in the production of fertilizers and explosives and rocket fuels
nitric oxide - a poisonous red-brown gas (NO)
nitrification - the oxidation of ammonium compounds in dead organic material into nitrates and nitrites by soil bacteria (making nitrogen available to plants); the chemical process in which a nitro group is added to an organic compound (or substituted for another group in an organic compound)
nitrile - any of a class of organic compounds containing the cyano radical -CN
nitrofurantoin - derivative of nitrofuran used as an antibacterial medicine (trade name Macrodantin) effective against a broad range of Gram-positive and Gram-negative bacteria; used to treat infections of the urinary tract
nitrogen dioxide - a highly poisonous brown gas (NO2)
nitrogen fixation - the assimilation of atmospheric nitrogen by soil bacteria and its release for plant use on the death of the bacteria
nitrogen oxide - any of several oxides of nitrogen formed by the action of nitric acid on oxidizable materials; present in car exhausts
nitrogen - a common nonmetallic element that is normally a colorless odorless tasteless inert diatomic gas; constitutes 78 percent of the atmosphere by volume; a constituent of all living tissues
nitrogenase - an enzyme of nitrogen-fixing microorganisms that catalyzes the conversion of nitrogen to ammonia
nitroglycerin - a heavy yellow poisonous oily explosive liquid obtained by nitrating glycerol; used in making explosives and medically as a vasodilator (trade names Nitrospan and Nitrostat)
nitrous oxide - inhalation anesthetic used as an anesthetic in dentistry and surgery
nocturia - excessive urination at night; especially common in older men
nodule - a small node; (mineralogy) a small rounded lump of mineral substance (usually harder than the surrounding rock or sediment); small rounded wartlike protuberance on a plant
noma - acute ulceration of the mucous membranes of the mouth or genitals; often seen in undernourished children
none - not any; not at all or in no way; a service in the Roman Catholic Church formerly read or chanted at 3 PM (the ninth hour counting from sunrise) but now somewhat earlier; a canonical hour that is the ninth hour of the day counting from sunrise
norepinephrine - a catecholamine precursor of epinephrine that is secreted by the adrenal medulla and also released at synapses
norethindrone - a synthetic progestational hormone (trade name Norlutin) used in oral contraceptives and to treat endometriosis
norgestrel - synthetic progestin used in oral contraceptives
nortriptyline - a tricyclic antidepressant drug (trade name Pamelor) used along with psychotherapy to treat dysthymic depression; may interact dangerously if taken with other drugs
nose - a front that resembles a human nose (especially the front of an aircraft); the front or forward projection of a tool or weapon; the organ of smell and entrance to the respiratory tract; the prominent part of the face of man or other mammals; a natural skill; the sense of smell (especially in animals); a symbol of inquisitiveness; a small distance; a projecting spout from which a fluid is discharged; verb defeat by a narrow margin; push or move with the nose; advance the forward part of with caution; rub noses; catch the scent of; get wind of; search or inquire in a meddlesome way
novobiocin - an antibiotic obtained from an actinomycete and used to treat infections by Gram-positive bacteria
nuclear medicine - the branch of medicine that uses radioactive materials either to image a patient's body or to destroy diseased cells
nucleic acid - (biochemistry) any of various macromolecules composed of nucleotide chains that are vital constituents of all living cells
nucleolus - a small round body of protein in a cell nucleus; such organelles contain RNA and are involved in protein synthesis
nucleoplasm - the protoplasm that constitutes the nucleus of a cell
nucleoprotein - any of several substances found in the nuclei of all living cells; consists of a protein bound to a nucleic acid
nucleoside - a glycoside formed by partial hydrolysis of a nucleic acid
nucleotide - a phosphoric ester of a nucleoside; the basic structural unit of nucleic acids (DNA or RNA)
numerator - the dividend of a fraction
numerous - amounting to a large indefinite number
nurse practitioner - a registered nurse who has received special training and can perform many of the duties of a physician
nurse - one skilled in caring for young children or the sick (usually under the supervision of a physician); a woman who is the custodian of children; verb try to cure by special care of treatment, of an illness or injury; treat carefully; serve as a nurse; care for sick or handicapped people; give suck to; maintain (a theory, thoughts, or feelings)
nursing home - an institution where people are cared for
nursing - the work of caring for the sick or injured or infirm; nourishing at the breast; the profession of a nurse
nutrition - the scientific study of food and drink (especially in humans); (physiology) the organic process of nourishing or being nourished; the processes by which an organism assimilates food and uses it for growth and maintenance; a source of materials to nourish the body
nystagmus - involuntary movements of the eyeballs; its presence or absence is used to diagnose a variety of neurological and visual disorders
nystatin - an antifungal and antibiotic (trade names Mycostatin and Nystan) discovered in New York State; derived from soil fungi actinomycetes
obesity - more than average fatness
obstetrics - the branch of medicine dealing with childbirth and care of the mother
obstruction - getting in someone's way; the act of obstructing; any structure that makes progress difficult; the state or condition of being obstructed; something immaterial that stands in the way and must be circumvented or surmounted
occipital lobe - that part of the cerebral cortex in either hemisphere of the brain lying in the back of the head
occlusion - (dentistry) the normal spatial relation of the teeth when the jaws are closed; closure or blockage (as of a blood vessel); the act of blocking; an obstruction in a pipe or tube; (meteorology) a composite front when colder air surrounds a mass of warm air and forces it aloft
occupation - the act of occupying or taking possession of a building; the principal activity in your life that you do to earn money; any activity that occupies a person's attention; the control of a country by military forces of a foreign power; the period of time during which a place or position or nation is occupied
occupational disease - disease or disability resulting from conditions of employment (usually from long exposure to a noxious substance or from continuous repetition of certain acts)
occupational therapy - physical therapy involving the therapeutic use of crafts and hobbies for the rehabilitation of handicapped or convalescing patients (especially for emotionally disturbed patients)
ochronosis - an accumulation of dark pigment in cartilage and other connective tissue; usually a symptom of alkaptonuria or phenol poisoning
oculomotor nerve - supplies extrinsic muscles of the eye
oil - oil paint containing pigment that is used by an artist; a slippery or viscous liquid or liquefiable substance not miscible with water; any of a group of liquid edible fats that are obtained from plants; verb cover with oil, as if by rubbing; administer an oil or ointment to ; often in a religious ceremony of blessing
ointment - semisolid preparation (usually containing a medicine) applied externally as a remedy or for soothing an irritation; toiletry consisting of any of various substances in the form of a thick liquid that have a soothing and moisturizing effect when applied to the skin
oleic acid - a colorless oily liquid occurring as a glyceride; it is the major fatty acid in olive oil and canola oil; used in making soap and cosmetics and ointments and lubricating oils
olfaction - the faculty that enables us to distinguish scents
olfactory bulb - one of two enlargements at the terminus of the olfactory nerve at the base of the brain just above the nasal cavities
olfactory nerve - a collective term for numerous olfactory filaments in the nasal mucosa
oligodendroglia - tissue consisting of glial cells with sheetlike processes that form the myelin sheath of nerve fibers
oligomenorrhea - abnormally light or infrequent menstruation
oligosaccharide - any of the carbohydrates that yield only a few monosaccharide molecules on complete hydrolysis
oligospermia - insufficient spermatozoa in the semen
oliguria - production of an abnormally small amount of urine; abnormally small production of urine; can be a symptom of kidney disease or obstruction of the urinary tract or edema or an imbalance of fluids and electrolytes in the body
omasum - the third compartment of the stomach of a ruminant
omentum - a fold of peritoneum supporting the viscera
omeprazole - antacid (trade name Prilosec) that suppresses acid secretion in the stomach
onchocerciasis - infestation with slender threadlike roundworms (filaria) deposited under the skin by the bite of black fleas; when the eyes are involved it can result in blindness; common in Africa and tropical America
oncogene - a gene that causes normal cells to change into cancerous tumor cells
oncologist - a specialist in oncology
oncology - the branch of medicine concerned with the study and treatment of tumors
onycholysis - separation of a nail from its normal attachment to the nail bed
oocyte - a female gametocyte that develops into an ovum after two meiotic divisions
oogenesis - development of ova
oophoritis - inflammation of one or both ovaries
operant conditioning - conditioning in which an operant response is brought under stimulus control by virtue of presenting reinforcement contingent upon the occurrence of the operant response
operon - a segment of DNA containing adjacent genes including structural genes and an operator gene and a regulatory gene
ophthalmologist - a medical doctor specializing in the treatment of diseases of the eye
ophthalmoplegia - paralysis of the motor nerves of the eye
ophthalmoscope - medical instrument for examining the retina of the eye
ophthalmoscopy - examination of the interior of an eye using an ophthalmoscope
opiate - a narcotic drug that contains opium or an opium derivative
opportunistic infection - any infection caused by a microorganism that does not normally cause disease in humans; occurs in persons with abnormally functioning immune systems (as AIDS patients or transplant patients receiving immunosuppressive drugs)
opsonin - an antibody in blood serum that attaches to invading microorganisms and other antigens to make them more susceptible to the action of phagocytes
optic chiasma - the crossing of the optic nerves from the two eyes at the base of the brain
optic disk - the point where the optic nerve enters the retina; not sensitive to light
optic nerve - the cranial nerve that serves the retina
optic tract - the cranial nerve that serves the retina
optical illusion - an optical phenomenon that results in a false or deceptive visual impression
optimism - a general disposition to expect the best in all things; the optimistic feeling that all is going to turn out well
oral - a stage in psychosexual development when the child's interest is concentrated in the mouth; fixation at this stage is said to result in dependence, selfishness, and aggression; of or involving the mouth or mouth region or the surface on which the mouth is located; using speech rather than writing; of or relating to or affecting or for use in the mouth; an examination conducted by word of mouth
orchiectomy - surgical removal of one or both testicles
orchitis - inflammation of one or both testes; characterized by pain and swelling
order coleoptera - beetles
order spirochaetales - higher bacteria; slender spiral rodlike forms
organ - wind instrument whose sound is produced by means of pipes arranged in sets supplied with air from a bellows and controlled from a large complex musical keyboard; a fully differentiated structural and functional unit in an animal that is specialized for some particular function; a periodical that is published by a special interest group; a government agency or instrument devoted to the performance of some specific function; (music) an electronic simulation of a pipe organ; a free-reed instrument in which air is forced through the reeds by bellows
organelle - a specialized part of a cell; analogous to an organ
organism - a living thing that has (or can develop) the ability to act or function independently; a system considered analogous in structure or function to a living body
orgasm - the moment of most intense pleasure in sexual intercourse
ornithine - an amino acid that does not occur in proteins but is important in the formation of urea
oropharyngeal - of or relating to or located near the oropharynx
orphenadrine - a skeletal muscle relaxant (trade name Norflex) used to treat severe muscle strain and Parkinsonism
orthodontics - the branch of dentistry dealing with the prevention or correction of irregularities of the teeth
orthodontist - a dentist specializing in the prevention or correction of irregularities of the teeth
orthopedics - the branch of medical science concerned with disorders or deformities of the spine and joints
orthoptera - grasshoppers and locusts; crickets
orthostatic hypotension - low blood pressure occurring in some people when they stand up
osmium - a hard brittle blue-grey or blue-black metallic element that is one of the platinum metals; the heaviest metal known
osteitis deformans - a disease of bone occurring in the middle aged and elderly; excessive bone destruction sometimes leading to bone pain and fractures and skeletal deformities
osteitis - inflammation of a bone as a consequence of infection or trauma or degeneration
osteoarthritis - chronic breakdown of cartilage in the joints; the most common form of arthritis occurring usually after middle age
osteoblast - a cell from which bone develops
osteoblastoma - benign tumor of bone and fibrous tissue; occurs in the vertebrae or femur or tibia or arm bones (especially in young adults)
osteochondroma - benign tumor containing both bone and cartilage; usually occurs near the end of a long bone
osteoclast - cell that functions in the breakdown and resorption of bone tissue
osteocyte - mature bone cell
osteogenesis imperfecta - autosomal dominant disorder of connective tissue characterized by brittle bones that fracture easily
osteolysis - lysis of bone caused by disease or infection or inadequate blood supply
osteoma - a slow growing benign tumor of consisting of bone tissue; usually on the skull or mandible
osteomalacia - abnormal softening of bones caused by deficiencies of phosphorus or calcium or vitamin D
osteomyelitis - an inflammation of bone and bone marrow (usually caused by bacterial infection)
osteopetrosis - an inherited disorder characterized by an increase in bone density; in severe forms the bone marrow cavity may be obliterated
osteophyte - small abnormal bony outgrowth
osteoporosis - abnormal loss of bony tissue resulting in fragile porous bones attributable to a lack of calcium; most common in postmenopausal women
osteosarcoma - malignant bone tumor; most common in children and young adults where it tends to affect the femur
osteosclerosis - abnormal hardening or eburnation of bone
osteotomy - surgical sectioning of bone
ostomy - surgical procedure that creates an artificial opening for the elimination of bodily wastes
other - very unusual; different in character or quality from the normal or expected; recently past; not the same one or ones already mentioned or implied; belonging to the distant past
otitis externa - inflammation of the external ear (including auricle and ear canal)
otitis media - inflammation of the middle ear; common in children
otolaryngologist - a specialist in the disorders of the ear or nose or throat
otosclerosis - hereditary disorder in which ossification of the labyrinth of the inner ear causes tinnitus and eventual deafness
otoscope - medical instrument consisting of a magnifying lens and light; used for examining the external ear (the auditory meatus and especially the tympanic membrane)
ounce - a unit of weight equal to one sixteenth of a pound or 16 drams or 28.349 grams; a unit of apothecary weight equal to 480 grains or one twelfth of a pound; large feline of upland central Asia having long thick whitish fur
outpatient - a patient who does not reside in the hospital where he is being treated
ovalbumin - the white part of an egg; the nutritive and protective gelatinous substance surrounding the yolk consisting mainly of albumin dissolved in water
ovarian cyst - a cystic tumor (usually benign) of the ovary
ovariectomy - surgical removal of one of both ovaries
ovary - (vertebrates) one of usually two organs that produce ova and secrete estrogen and progesterone; the organ that bears the ovules of a flower
overbite - (dentistry) malocclusion in which the upper teeth extend abnormally far over the lower teeth
overdose - verb dose too heavily
overweight - usually describes a large person who is fat but has a large frame to carry it; the property of excessive fatness
ovotestis - hermaphroditic gonad that contains both testicular and ovarian tissue
ovulation - the expulsion of an ovum from the ovary (usually midway in the menstrual cycle)
ovum - the female reproductive cell; the female gamete
oxacillin - a form of penicillin resistant to penicillinase and effective against penicillin-resistant staphylococci
oxaloacetate - a salt or ester of oxalacetic acid
oxazepam - a tranquilizing drug (trade name Serax) used to treat anxiety and insomnia and alcohol withdrawal
oxidation-reduction - a reversible chemical reaction in which one reaction is an oxidation and the reverse is a reduction
oxidation - the process of oxidizing; the addition of oxygen to a compound with a loss of electrons; always occurs accompanied by reduction
oxidative phosphorylation - an enzymatic process in cell metabolism that synthesizes ATP from ADP
oxide - any compound of oxygen with another element or a radical
oxidoreductase - an enzyme that catalyzes oxidation-reduction
oxime - any compound containing the group -C=NOH
oximeter - a measuring instrument that measures the oxygen in arterial blood
oxygen - a nonmetallic bivalent element that is normally a colorless odorless tasteless nonflammable diatomic gas; constitutes 21 percent of the atmosphere by volume; the most abundant element in the earth's crust
oxyhemoglobin - the bright red hemoglobin that is a combination of hemoglobin and oxygen from the lungs
oxytocic - a drug that induces labor by stimulating contractions of the muscles of the uterus
oxytocin - hormone secreted by the posterior pituitary gland (trade name Pitocin); stimulates contractions of the uterus and ejection of milk
ozone - a colorless gas (O3) soluble in alkalis and cold water; a strong oxidizing agent; can be produced by electric discharge in oxygen or by the action of ultraviolet radiation on oxygen in the stratosphere (where it acts as a screen for ultraviolet radiation)
pacifier - device used for an infant to suck or bite on; someone who tries to bring peace
pacinian corpuscle - a specialized bulblike nerve ending located in the subcutaneous tissue of the skin; occurs abundantly in the skin of palms and soles and joints and genitals
pain threshold - the lowest intensity of stimulation at which pain is experienced
pain - a somatic sensation of acute discomfort; emotional distress; a fundamental feeling that people try to avoid; a bothersome annoying person; a symptom of some physical hurt or disorder; something or someone that causes trouble; a source of unhappiness; verb cause emotional anguish or make miserable; cause bodily suffering to and make sick or indisposed
palate - the upper surface of the mouth that separates the oral and nasal cavities
palatine tonsil - either of two masses of lymphatic tissue one on each side of the oral pharynx
palladium - a silver-white metallic element of the platinum group that resembles platinum; occurs in some copper and nickel ores; does not tarnish at ordinary temperatures and is used (alloyed with gold) in jewelry
pallor - unnatural lack of color in the skin (as from bruising or sickness or emotional distress)
palmitic acid - a saturated fatty acid that is the major fat in meat and dairy products
palpable - capable of being perceived by the senses or the mind; especially capable of being handled or touched or felt; can be felt by palpation
palpation - a method of examination in which the examiner feels the size or shape or firmness or location of something (of body parts when the examiner is a health professional)
palpitation - a rapid and irregular heart beat; a shaky motion
palsy - a condition marked by uncontrollable tremor; loss of the ability to move a body part; verb affect with palsy
panax - perennial herbs of eastern North America and Asia having aromatic tuberous roots: ginseng
pancreas - a large elongated exocrine gland located behind the stomach; secretes pancreatic juice and insulin
pancreatectomy - surgical removal of part or all of the pancreas
pancreatic duct - a duct connecting the pancreas with the intestine
pancreatic juice - a fluid secreted into the duodenum by the pancreas; important for breaking down starches and proteins and fats
pancreatitis - inflammation of the pancreas; usually marked by abdominal pain
pancytopenia - an abnormal deficiency in all blood cells (red blood cells and white blood cells and platelets); usually associated with bone marrow tumor or with aplastic anemia
panic attack - a sudden attack of fear
panic disorder - an anxiety disorder characterized by unpredictable panic attacks; the attacks are usually severe but brief
panic - an overwhelming feeling of fear and anxiety; sudden mass fear and anxiety over anticipated events; verb cause sudden fear in or fill with sudden panic; be overcome by a sudden fear
pantothenic acid - a vitamin of the vitamin B complex that performs an important role in the oxidation of fats and carbohydrates and certain amino acids; occurs in many foods
pap smear - a sample of secretions and superficial cells of the uterine cervix and uterus; examined with a microscope to detect any abnormal cells
papain - a proteolytic enzyme obtained from the unripe papaya; used as a meat tenderizer
papaverine - an alkaloid medicine (trade name Kavrin) obtained from opium; used to relax smooth muscles; it is nonaddictive
papillary muscle - any of several muscles associated with the atrioventricular valves
papilledema - swelling of the optic disc (where the optic nerve enters the eyeball); usually associated with an increase in intraocular pressure
papilloma - a benign epithelial tumor forming a rounded mass
papovavirus - any of a group of animal viruses associated with or causing papillomas or polyomas
paracentesis - centesis of the belly to remove fluid for diagnosis
paraffin - (British usage) kerosine; from crude petroleum; used for candles and for preservative or waterproof coatings; a series of non-aromatic saturated hydrocarbons with the general formula CnH(2n+2)
paralysis - loss of the ability to move a body part
paramecium - any member of the genus Paramecium
paramyxovirus - a group of viruses including those causing mumps and measles
paranoia - a psychological disorder characterized by delusions of persecution or grandeur
paranoid schizophrenia - a form of schizophrenia characterized by delusions (of persecution or grandeur or jealousy); symptoms may include anger and anxiety and aloofness and doubts about gender identity; unlike other types of schizophrenia the patients are usually presentable and (if delusions are not acted on) may function in an apparently normal manner
paraparesis - a slight paralysis or weakness of both legs
paraplegia - paralysis of the lower half of the body (most often as a result of trauma)
paraquat - a poisonous yellow solid used in solution as a herbicide
parasite - an animal or plant that lives in or on a host (another animal or plant); it obtains nourishment from the host without benefiting or killing the host; a follower who hangs around a host (without benefit to the host) in hope of gain or advantage
parathion - a colorless and odorless toxic oil used as an insecticide
parathyroid gland - any one of four endocrine glands situated above or within the thyroid gland
parathyroid hormone - hormone synthesized and released into the blood stream by the parathyroid glands; regulates phosphorus and calcium in the body and functions in neuromuscular excitation and blood clotting
paratyphoid fever - any of a variety of infectious intestinal diseases resembling typhoid fever
parenchyma - animal tissue that constitutes the essential part of an organ as contrasted with e.g. connective tissue and blood vessels; the primary tissue of higher plants composed of thin-walled cells that remain capable of cell division even when mature; constitutes the greater part of leaves, roots, the pulp of fruits, and the pith of stems
parent - a father or mother; one who begets or one who gives birth to or nurtures and raises a child; a relative who plays the role of guardian; verb bring up
paresis - a slight or partial paralysis
paresthesia - abnormal skin sensations (as tingling or tickling or itching or burning) usually associated with peripheral nerve damage
parietal lobe - that part of the cerebral cortex in either hemisphere of the brain lying below the crown of the head
parietal pleura - pleura that lines the inner chest walls and covers the diaphragm
parity - functional equality; (physics) parity is conserved in a universe in which the laws of physics are the same in a right-handed system of coordinates as in a left-handed system; (mathematics) a relation between a pair of integers: if both integers are odd or both are even they have the same parity; if one is odd and the other is even they have different parity; (obstetrics) the number of liveborn children a woman has delivered; (computer science) a bit that is used in an error detection procedure in which a 0 or 1 is added to each group of bits so that it will have either an odd number of 1's or an even number of 1's; e.g., if the parity is odd then any group of bits that arrives with an even number of 1's must contain an error
parkinson's disease - a degenerative disorder of the central nervous system characterized by tremor and impaired muscular coordination
parkinsonism - a degenerative disorder of the central nervous system characterized by tremor and impaired muscular coordination
paronychia - low-growing annual or perennial herbs or woody plants; whitlowworts; infection in the tissues adjacent to a nail on a finger or toe
parotid gland - a large salivary gland that produces 50% of daytime saliva; in human beings it is located in front of and below each ear
parotitis - inflammation of one or both parotid glands
parthenogenesis - process in which an unfertilized egg develops into a new individual; common among insects and some other arthropods; human conception without fertilization by a man
partial - being or affecting only a part; not total; showing favoritism; (followed by `of' or `to') having a strong preference or liking for; a harmonic with a frequency that is a multiple of the fundamental frequency; the derivative of a function of two or more variables with respect to a single variable while the other variables are considered to be constant
participation - the condition of sharing in common with others (as fellows or partners etc.); the act of sharing in the activities of a group
parvovirus - any of a group of viruses containing DNA in an icosahedral protein shell and causing disease in dogs and cattle; not known to be associated with any human disease
paste - an adhesive made from water and flour or starch; used on paper and paperboard; any mixture of a soft and malleable consistency; a tasty mixture to be spread on bread or crackers; verb cover the surface of; hit with the fists; join or attach with or as if with glue
patch test - a test to determine allergic sensitivity by applying small pads soaked with allergen to the unbroken skin
patch - a piece of cloth used as decoration or to mend or cover a hole; a short set of commands to correct a bug in a computer program; a piece of soft material that covers and protects an injured part of the body; a protective cloth covering for an injured eye; sewing that repairs a worn or torn hole (especially in a garment); a connection intended to be used for a limited time; a small contrasting part of something; a small area of ground covered by specific vegetation; a period of indeterminate length (usually short) marked by some action or condition; verb mend by putting a patch on; to join or unite the pieces of; provide with a patch; also used metaphorically; repair by adding pieces
patella - type genus of the family Patellidae: common European limpets; a small flat triangular bone in front of the knee that protects the knee joint
patent ductus arteriosus - a ductus arteriosus that failed to close at birth; may require surgical correction
pathogen - any disease-producing agent (especially a virus or bacterium or other microorganism)
pathogenesis - the origination and development of a disease
pathologic process - an organic process occurring as a consequence of disease
pathologist - a doctor who specializes in medical diagnosis
pathology - the branch of medical science that studies the causes and nature and effects of diseases; any deviation from a healthy or normal condition
patient - enduring without protest or complaint; enduring trying circumstances with even temper or characterized by such endurance; a person who requires medical care; the semantic role of an entity that is not the agent but is directly involved in or affected by the happening denoted by the verb in the clause
peanut oil - a oil from peanuts; used in cooking and making soap
pectin - any of various water-soluble colloidal carbohydrates that occur in ripe fruit and vegetables; used in making fruit jellies and jams
pediatrics - the branch of medicine concerned with the treatment of infants and children
pedigree - having a list of ancestors as proof of being a purebred animal; ancestry of a purebred animal; line of descent of a purebred animal; the descendants of one individual
pedophilia - a sexual attraction to children
pedunculate - having or growing on or from a peduncle or stalk
peer review - verb evaluate professionally a colleague's work
pellagra - a disease caused by deficiency of niacin or tryptophan (or by a defect in the metabolic conversion of tryptophan to niacin); characterized by gastrointestinal disturbances and erythema and nervous or mental disorders; may be caused by malnutrition or alcoholism or other nutritional impairments
pellet - a small sphere; a solid missile discharged from a firearm
pelvic girdle - the structure of the vertebrate skeleton supporting the lower limbs in humans and the hind limbs or corresponding parts in other vertebrates
pelvic inflammatory disease - inflammation of the female pelvic organs (especially the Fallopian tubes) caused by infection by any of several microorganisms (chiefly gonococci and chlamydia); symptoms are abdominal pain and fever and foul-smelling vaginal discharge
pelvis - a structure shaped like a funnel in the outlet of the kidney into which urine is discharged before passing into the ureter; the structure of the vertebrate skeleton supporting the lower limbs in humans and the hind limbs or corresponding parts in other vertebrates
pemphigus - a skin disease characterized by large thin-walled blisters (bullae) arising from normal skin or mucous membrane
penicillamine - a drug (trade name Cuprimine) used to treat heavy metal poisoning and Wilson's disease and severe arthritis
penicillin g - the penicillin that constitutes the principal component of many commercial antibiotics
penicillin v - a crystalline penicillin similar in action to penicillin G but more resistant to the action of gastric acids
penicillin - any of various antibiotics obtained from Penicillium molds (or produced synthetically) and used in the treatment of various infections and diseases
penicillium - genus of fungi commonly growing as green or blue molds on decaying food; used in making cheese and as a source of penicillin
penis - the male organ of copulation (`member' is a euphemism)
pentobarbital - a barbiturate (trade name Nembutal) used as a sedative and hypnotic and antispasmodic
pentose - any monosaccharide sugar containing five atoms of carbon per molecule
pentoxifylline - a drug (trade name Trental) used to treat claudication; believed to increase the flexibility of red blood cells so they can flow through the blood vessels to the legs and feet
pepsinogen - precursor of pepsin; stored in the stomach walls and converted to pepsin by hydrochloric acid in the stomach
peptic ulcer - an ulcer of the mucous membrane lining of the alimentary tract
peptide - amide combining the amino group of one amino acid with the carboxyl group of another; usually obtained by partial hydrolysis of protein
perception - the process of perceiving; knowledge gained by perceiving; a way of conceiving something; becoming aware of something via the senses; the representation of what is perceived; basic component in the formation of a concept
perforation - the act of punching a hole (especially a row of holes as for ease of separation); a line of small holes for tearing at a particular place; a hole made in something
performance - any recognized accomplishment; the act of performing; of doing something successfully; using knowledge as distinguished from merely possessing it; the act of presenting a play or a piece of music or other entertainment; a dramatic or musical entertainment; process or manner of functioning or operating
perfusion - pumping a liquid into an organ or tissue (especially by way of blood vessels)
perianal - around the anus
periarteritis nodosa - a progressive disease of connective tissue that is characterized by nodules along arteries; nodules may block the artery and result in inadequate circulation to the particular area
pericardial cavity - the space between the layers of the pericardium that contains fluid that lubricates the membrane surfaces and allows easy heart movement
pericarditis - inflammation of the pericardium
pericardium - a serous membrane with two layers that surrounds the heart
perilymph - the bodily fluid that fills the space between the bony labyrinth and the membranous labyrinth of the inner ear
perineum - the general region between the anus and the genital organs
periodic acid - any acid of iodine that contains oxygen
periodontist - a dentist specializing in diseases of the gums and other structure surrounding the teeth
periodontitis - a disease that attacks the gum and bone and around the teeth
periosteum - a dense fibrous membrane covering the surface of bones (except at their extremities) and serving as an attachment for tendons and muscles; contains nerves and blood vessels that nourish the enclosed bone
peripheral nervous system - the section of the nervous system lying outside the brain and spinal cord
peristalsis - the process of wavelike muscle contractions of the alimentary tract that moves food along
peritoneal cavity - the interior of the peritoneum; a potential space between layers of the peritoneum
peritoneal - of or relating to or affecting the peritoneum
peritoneum - a transparent membrane that lines the abdominal cavity in mammals and covers most of the viscera
peritonitis - inflammation of the peritoneum
peritonsillar abscess - a painful pus filled inflammation of the tonsils and surrounding tissues; usually a complication of tonsillitis
pernicious anemia - a chronic progressive anemia of older adults; thought to result from a lack of intrinsic factor (a substance secreted by the stomach that is responsible for the absorption of vitamin B12)
peroxidase - any of a group of enzymes (occurring especially in plant cells) that catalyze the oxidation of a compound by a peroxide
perphenazine - tranquilizer and antidepressant (trade name Triavil) sometimes used as an antiemetic for adults
perseveration - the tendency for a memory or idea to persist or recur without any apparent stimulus for it; the act of persisting or persevering; continuing or repeating behavior
personality disorder - inflexible and maladaptive patterns of behavior
personality test - any test that is intended to assess personality
personality - the complex of all the attributes--behavioral, temperamental, emotional and mental--that characterize a unique individual; a person of considerable prominence
pertussis - a disease of the respiratory mucous membrane
pessary - a contraceptive device consisting of a flexible dome-shaped cup made of rubber or plastic; it is filled with spermicide and fitted over the uterine cervix
pessimism - a general disposition to look on the dark side and to expect the worst in all things; the feeling that things will turn out badly
pesticide - a chemical used to kill pests (as rodents or insects)
petechia - a minute red or purple spot on the surface of the skin as the result of tiny hemorrhages of blood vessels in the skin (as in typhoid fever)
petrolatum - a semisolid mixture of hydrocarbons obtained from petroleum; used in medicinal ointments and for lubrication
phagocyte - a cell that engulfs and digests debris and invading microorganisms
phagocytosis - process in which phagocytes engulf and digest microorganisms and cellular debris; an important defense against infection
phantom limb - the illusion that a limb still exists after it has been amputated
pharmacist - a health professional trained in the art of preparing and dispensing drugs
pharmacogenetics - the branch of genetics that studies the genetically determined variations in responses to drugs in humans or laboratory organisms
pharmacokinetics - the study of the action of drugs in the body: method and rate of excretion; duration of effect; etc.
pharmacology - the science or study of drugs: their preparation and properties and uses and effects
pharyngitis - inflammation of the fauces and pharynx
pharynx - the passage to the stomach and lungs; in the front part of the neck below the chin and above the collarbone
phenacetin - a white crystalline compound used as an analgesic and also as an antipyretic
phenazopyridine - analgesic (trade name Pyridium) used to treat urinary tract infections
phencyclidine - a drug used as an anesthetic by veterinarians; illicitly taken (originally in the form of powder or `dust') for its effects as a hallucinogen
phenelzine - monoamine oxidase inhibitor (trade name Nardil) used to treat clinical depression
phenobarbital - a long-acting barbiturate used as a sedative
phenol - any of a class of weakly acidic organic compounds; molecule contains one or more hydroxyl groups; a toxic white soluble crystalline acidic derivative of benzene; used in manufacturing and as a disinfectant and antiseptic; poisonous if taken internally
phenolphthalein - a laxative used in many preparations under various trade names; also used as an acid-base indicator in titrations involving weak acids and strong bases because it is brilliant red at high alkalinity and colorless below pH 8
phenothiazine - a compound used primarily in veterinary medicine to rid farm animals of internal parasites
phenotype - what an organism looks like as a consequence of the interaction of its genotype and the environment
phentolamine - a virility drug (trade name Vasomax) to treat erectile dysfunction in men
phenylalanine - an essential amino acid found in proteins and needed for growth of children and for protein metabolism in children and adults; abundant in milk and eggs; it is normally converted to tyrosine in the human body
phenylephrine - a powerful vasoconstrictor used to dilate the pupils and relieve nasal congestion
phenylketonuria - a genetic disorder of metabolism; lack of the enzyme needed to turn phenylalanine into tyrosine results in an accumulation of phenylalanine in the body fluids which causes various degrees of mental deficiency
phenylpropanolamine - an adrenergic drug used in many preparations to relieve allergic reactions or respiratory infections
phenytoin - an anticonvulsant drug (trade name Dilantin) used to treat epilepsy and that is not a sedative
pheochromocytoma - a vascular tumor of the adrenal gland; hypersecretion of epinephrine results in intermittent or sustained hypertension
pheromone - a chemical substance secreted externally by some animals (especially insects) that influences the physiology or behavior of other animals of the same species
phimosis - an abnormal tightness of the foreskin preventing retraction over the glans
phlebitis - inflammation of a vein (usually in the legs)
phlebotomy - surgical incision into a vein; used to treat hemochromatosis
phlegm - expectorated matter; saliva mixed with discharges from the respiratory passages; in ancient and medieval physiology it was believed to cause sluggishness; inactivity; showing an unusual lack of energy; apathy demonstrated by an absence of emotional reactions
phobia - an anxiety disorder characterized by extreme and irrational fear of simple things or social situations
phocomelia - an abnormality of development in which the upper part of an arm or leg is missing so the hands or feet are attached to the body like stumps; rare condition that results from taking thalidomide during pregnancy
phonation - the sound made by the vibration of vocal folds modified by the resonance of the vocal tract
phonophobia - a morbid fear of sounds including your own voice
phosphocreatine - an organic compound of creatine and phosphoric acid; found in the muscles of vertebrates where its hydrolysis releases energy for muscular contraction
phospholipid - any of various compounds composed of fatty acids and phosphoric acid and a nitrogenous base; an important constituent of membranes
phosphoric acid - an acid used in fertilizers and soaps: H3PO4
phosphorus - a multivalent nonmetallic element of the nitrogen family that occurs commonly in inorganic phosphate rocks and as organic phosphates in all living cells; is highly reactive and occurs in several allotropic forms; a planet (usually Venus) seen just before sunrise in the eastern sky
photochemistry - branch of chemistry that deals with the chemical action of light
photometer - measuring instrument for measuring the luminous intensity of a source by comparing it (visually or photoelectrically) with a standard source; photographic equipment that measures the intensity of light
photometry - measurement of the properties of light (especially luminous intensity)
photon - a quantum of electromagnetic radiation; an elementary particle that is its own antiparticle
photophobia - a morbid fear of light; pain in the eye resulting from exposure to bright light (often associated with albinism)
phototherapy - the use of strong light to treat acne or hyperbilirubinemia of the newborn
phototropism - an orienting response to light
phrenic nerve - one of a pair of nerves that arises from cervical spinal roots and passes down the thorax to innervate the diaphragm and control breathing
physical fitness - good physical condition; being in shape or in condition
physical therapy - therapy that uses physical agents: exercise and massage and other modalities
physician - a licensed medical practitioner
physics - the science of matter and energy and their interactions
physiological - of or relating to the biological study of physiology; of or consistent with an organism's normal functioning
physiology - processes and functions of an organism; the branch of the biological sciences dealing with the functioning of organisms
physostigmine - used in treatment of Alzheimer's disease and glaucoma
phytotherapy - the use of plants or plant extracts for medicinal purposes (especially plants that are not part of the normal diet)
pia mater - the highly vascular innermost of the 3 meninges
picometer - a metric unit of length equal to one trillionth of a meter
picosecond - one trillionth (10^-12) of a second; one thousandth of a nanosecond
pigmentation - coloration of living tissues by pigment; the deposition of pigment in animals or plants or human beings
pill - a dose of medicine in the form of a small pellet; something that resembles a tablet of medicine in shape or size; a contraceptive in the form of a pill containing estrogen and progestin to inhibit ovulation and so prevent conception; something unpleasant or offensive that must be tolerated or endured; a unpleasant or tiresome person
pilocarpine - cholinergic alkaloid used in eyedrops to treat glaucoma
pilot project - activity planned as a test or trial
pimozide - the most commonly used diphenylbutyl piperidine
pindolol - an oral beta blocker (trade name Visken) used in treating hypertension
pineal - having the form of a pine cone; relating to the pineal body
pinguecula - a slightly elevated elastic tissue deposit in the conjunctiva that may extend to the cornea but does not cover it
pinocytosis - process by which certain cells can engulf and incorporate droplets of fluid
pint - a United States liquid unit equal to 16 fluid ounces; two pints equal one quart; a United States dry unit equal to 0.5 quart or 33.6 cubic inches; a British imperial capacity measure (liquid or dry) equal to 4 gills or 568.26 cubic centimeters
pinwheel - a toy consisting of vanes of colored paper or plastic that is pinned to a stick and spins when it is pointed into the wind; a wheel that has numerous pins that are set at right angles to its rim; perennial subshrub of Tenerife having leaves in rosettes resembling pinwheels; a circular firework that spins round and round emitting colored fire
piperacillin - a synthetic type of penicillin antibiotic (trade name Pipracil) used for moderate to severe infections
piroxicam - a nonsteroidal anti-inflammatory drug (trade name Feldene) used to treat arthritis and other inflammatory conditions
pisiform bone - a small wrist bone that articulates only with the triquetral
pituitary - of or relating to the pituitary gland; having abnormal size with overgrown extremities resulting from abnormal pituitary secretion; the master gland of the endocrine system; located at the base of the brain
pityriasis rosea - pityriasis in which an itchy rash develops over the trunk and extremities
placebo effect - any effect that seems to be a consequence of administering a placebo; the change is usually beneficial and is assumed result from the person's faith in the treatment or preconceptions about what the experimental drug was supposed to do; pharmacologists were the first to talk about placebo effects but now the idea has been generalized to many situations having nothing to do with drugs
placebo - (Roman Catholic Church) vespers of the office for the dead; an innocuous or inert medication; given as a pacifier or to the control group in experiments on the efficacy of a drug
placenta previa - pregnancy in which the placenta is implanted in the lower part of the uterus (instead of the upper part); can cause bleeding late in pregnancy; delivery by cesarean section may be necessary
placenta - the vascular structure in the uterus of most mammals providing oxygen and nutrients for and transferring wastes from the developing fetus; that part of the ovary of a flowering plant where the ovules form
placentation - arrangement of the ovules in the placenta and of the placentas in the ovary; the formation of the placenta in the uterus
plagiocephaly - congenital malformation of the skull in which the main axis of the skull is oblique
plague - an annoyance; any large scale calamity (especially when thought to be sent by God); any epidemic disease with a high death rate; a serious (sometimes fatal) infection of rodents caused by Yersinia pestis and accidentally transmitted to humans by the bite of a flea that has bitten an infected animal; a swarm of insects that attack plants; verb annoy continually or chronically; cause to suffer a blight
plant part - any part of a plant or fungus
plasma cell - a cell that develops from a B lymphocyte in reaction to a specific antigen; found in bone marrow and sometimes in the blood
plasma membrane - a thin membrane (a double layer of lipids) enclosing the cytoplasm of a cell; proteins in the membrane control passage of ions (like sodium or potassium or calcium) in and out of the cell
plasma - colorless watery fluid of blood and lymph containing no cells and in which erythrocytes and leukocytes and platelets are suspended; (physical chemistry) a fourth state of matter distinct from solid or liquid or gas and present in stars and fusion reactors; a gas becomes a plasma when it is heated until the atoms lose all their electrons, leaving a highly electrified collection of nuclei and free electrons; a green slightly translucent variety of chalcedony used as a gemstone
plasmacytoma - neoplasm of plasma cells (usually in bone marrow)
plasmapheresis - plasma is separated from whole blood and the rest is returned to the donor
plasmid - a small cellular inclusion consisting of a ring of DNA that is not in a chromosome but is capable of autonomous replication
plasmin - an enzyme that dissolves the fibrin of blood clots
plasminogen activator - protease produced in the kidney that converts plasminogen to plasmin and so initiates fibrinolysis
plasminogen - an inactive form of plasmin that occurs in plasma and is converted to plasmin by organic solvents
plasmodium vivax - parasitic protozoan of the genus Plasmodium that causes malaria in humans
plasmodium - parasitic protozoan of the genus Plasmodium that causes malaria in humans; multinucleate sheet of cytoplasm characteristic of some stages of such organisms as slime molds
plastic surgery - surgery concerned with therapeutic or cosmetic reformation of tissue
plastic - capable of being influenced or formed; forming or capable of forming or molding or fashioning; capable of being molded or modeled (especially of earth or clay or other soft material); generic name for certain synthetic or semisynthetic materials that can be molded or extruded into objects or films or filaments or used for making e.g. coatings and adhesives
plasticizer - a substance added to plastics or other materials to make them more pliable
plastid - any of various small particles in the cytoplasm of the cells of plants and some animals containing pigments or starch or oil or protein
platelet - tiny bits of protoplasm found in vertebrate blood; essential for blood clotting
platinum - a heavy precious metallic element; grey-white and resistant to corroding; occurs in some nickel and copper ores and is also found native in some deposits
platyhelminthes - flatworms
play therapy - form of psychotherapy for children that uses play situations for diagnosis or treatment
pleasure - sexual gratification; an activity that affords enjoyment; a formal expression; a fundamental feeling that is hard to define but that people desire to experience; something or someone that provides pleasure; a source of happiness
pleura - the thin serous membrane around the lungs and inner walls of the chest
pleural cavity - the cavity in the thorax that contains the lungs and heart
pleurisy - inflammation of the pleura of the lungs (especially the parietal layer)
pliability - adaptability of mind or character; the property of being easily bent without breaking
plutonium - a solid silvery grey radioactive transuranic element whose atoms can be split when bombarded with neutrons; found in minute quantities in uranium ores but is usually synthesized in nuclear reactors; 13 isotopes are known with the most important being plutonium 239
pneumococcal vaccine - vaccine (trade name Pneumovax) effective against the 23 most common strains of pneumococcus
pneumoconiosis - chronic respiratory disease caused by inhaling metallic or mineral particles
pneumocystis pneumonia - pneumonia occurring in infants or in persons with impaired immune systems (as AIDS victims)
pneumonectomy - surgical removal of a lung (usually to treat lung cancer)
pneumonia - respiratory disease characterized by inflammation of the lung parenchyma (excluding the bronchi) with congestion caused by viruses or bacteria or irritants
pneumonitis - inflammation of the lungs; caused by a virus or an allergic reaction
pneumothorax - abnormal presence of air in the pleural cavity resulting in the collapse of the lung; may be spontaneous (due to injury to the chest) or induced (as a treatment for tuberculosis)
point mutation - a mutation due to an intramolecular reorganization of a gene
poisoning - the act of giving poison to a person or animal with the intent to kill; the physiological state produced by a poison or other toxic substance
polarity - having an indicated pole (as the distinction between positive and negative electric charges); a relation between two opposite attributes or tendencies
polarography - an electrochemical method of chemical analysis
policy - a plan of action adopted by an individual or social group; written contract or certificate of insurance; a line of argument rationalizing the course of action of a government
poliomyelitis - an acute viral disease marked by inflammation of nerve cells of the brain stem and spinal cord
poliosis - loss of color from the hair
poliovirus vaccine - vaccine prepared from poliovirus to provide immunity to poliomyelitis
poliovirus - the virus causing poliomyelitis
pollen tube - (botany) a slender tubular outgrowth from a pollen grain when deposited on the stigma for a flower; it penetrates the style and conveys the male gametes to the ovule
pollination - transfer of pollen from the anther to the stigma of a plant
polycythemia - a disorder characterized by an abnormal increase in the number of red blood cells in the blood
polydactyly - birth defect characterized by the presence of more than the normal number of fingers or toes
polydipsia - excessive thirst (as in cases of diabetes or kidney dysfunction)
polyethylene - a lightweight thermoplastic; used especially in packaging and insulation
polymer - a naturally occurring or synthetic compound consisting of large molecules made up of a linked series of repeated simple monomers
polymyositis - myositis characterized by weakness of limb and neck muscles and much muscle pain and swelling; progression and severity vary among individuals
polyneuritis - inflammation of many or all of the peripheral nerves (as in leprosy)
polyoma virus - a virus the can initiate various kinds of tumors in mice
polyp - one of two forms that coelenterates take e.g. a hydra or coral: usually sedentary and has a hollow cylindrical body usually with a ring of tentacles around the mouth; a small vascular growth on the surface of a mucous membrane
polyploid - of a cell or organism having more than twice the haploid number of chromosomes; (genetics) an organism or cell having more than twice the haploid number of chromosomes
polypropylene - a polymer of propylene used as a thermoplastic molding material
polysaccharide - any of a class of carbohydrates whose molecules contain chains of monosaccharide molecules
polystyrene - a polymer of styrene; a rigid transparent thermoplastic
polyurethane - any of various polymers containing the urethane radical; a wide variety of synthetic forms are made and used as adhesives or plastics or paints or rubber
polyuria - renal disorder characterized by the production of large volumes of pale dilute urine; often associated with diabetes
pons - a band of nerve fibers linking the medulla oblongata and the cerebellum with the midbrain; United States coloratura soprano (born in France) (1904-1976)
porifera - coextensive with the subkingdom Parazoa: sponges
porphyria - a genetic abnormality of metabolism causing abdominal pains and mental confusion
porphyrin - any of various pigments distributed widely in living tissues
portal hypertension - increase in blood pressure in the veins of the portal system caused by obstruction in the liver (often associated with alcoholic cirrhosis), causing enlargement of the spleen and collateral veins
portal vein - a short vein that carries blood into the liver
positive - formally laid down or imposed; characterized by or displaying affirmation or acceptance or certainty etc.; greater than zero; reckoned, situated or tending in the direction which naturally or arbitrarily is taken to indicate increase or progress or onward motion; indicating existence or presence of a suspected condition or pathogen; having a positive electric charge; involving advantage or good; persuaded of; very sure; marked by excessive confidence; impossible to deny or disprove; of or relating to positivism; a film showing a photographic image whose tones correspond to those of the original subject
positron emission tomography - using a computerized radiographic technique to examine the metabolic activity in various tissues (especially in the brain)
postpartum - occurring immediately after birth
potassium chloride - salt of potassium (KCl) (trade names K-Dur 20, Kaochlor and K-lor and Klorvess and K-lyte); taken in tablet form to treat potassium deficiency
potassium dichromate - an orange-red salt used in making dyes and in photography
potassium iodide - a crystalline salt in organic synthesis and in making photographic emulsions and in iodized table salt
potassium - a light soft silver-white metallic element of the alkali metal group; oxidizes rapidly in air and reacts violently with water; is abundant in nature in combined forms occurring in sea water and in carnallite and kainite and sylvite
potential - existing in possibility; expected to become or be; in prospect; the inherent capacity for coming into being; the difference in electrical charge between two points in a circuit expressed in volts
poultice - a medical dressing consisting of a soft heated mass of meal or clay that is spread on a cloth and applied to the skin to treat inflamed areas or improve circulation etc.; verb dress by covering with a therapeutic substance
practitioner - someone who practices a learned profession
pravastatin - an oral drug (trade name Pravachol) administered to reduce blood cholesterol levels; recommended after nonfatal heart attacks
prazosin - antihypertensive drug (trade name Minipress)
pre-eclampsia - abnormal state of pregnancy characterized by hypertension and fluid retention and albuminuria; can lead to eclampsia if untreated
precursor - a person who goes before or ances the coming of another; a substance from which another substance is formed (especially by a metabolic reaction); an indication of the approach of something or someone
prednisolone - a glucocorticoid (trade names Pediapred or Prelone) used to treat inflammatory conditions
prednisone - a dehydrogenated analogue of cortisol (trade names Orasone or Deltasone or Liquid Pred or Meticorten); used as an anti-inflammatory drug in the treatment of arthritis and as an immunosuppressant
preference - grant of favor or advantage to one over another (especially to a country or countries in matters of international trade, such as levying duties); the right or chance to choose; a strong liking; a predisposition in favor of something
prefix - an affix that is added in front of the word; verb attach a prefix to
pregnancy test - a physiological test to determine whether a person is pregnant
pregnancy - the state of being pregnant; the period from conception to birth when a woman carries a developing fetus in her uterus
prejudice - a partiality that prevents objective consideration of an issue or situation; verb influence (somebody's) opinion in advance; disadvantage by prejudice
premature ejaculation - ejaculation during the early stages of sexual excitement or soon after the insertion of the penis into the vagina
premature labor - labor beginning prior to the 37th week of gestation
premenstrual syndrome - a syndrome that occurs in many women from 2 to 14 days before the onset of menstruation
prenatal diagnosis - any of the diagnostic procedures used to determine whether a fetus has a genetic abnormality
presbyopia - farsightedness resulting from a reduced ability to focus caused by loss of elasticity of the crystalline lens with age
presenile dementia - dementia with onset before the age of 65
preservation - the activity of protecting something from loss or danger; a process that saves organic substances from decay; the condition of being (well or ill) preserved; an occurrence of improvement by virtue of preventing loss or injury or other change
preservative - tending or having the power to preserve; a chemical compound that is added to protect against decay or decomposition
priapism - condition in which the penis is continually erect; usually painful and seldom with sexual arousal
primaquine - synthetic antimalarial drug
primidone - an anticonvulsant (trade name Mysoline) used to treat grand mal seizures and essential tremor
prion - (microbiology) an infectious protein particle similar to a virus but lacking nucleic acid; thought to be the agent responsible for scrapie and other degenerative diseases of the nervous system
privacy - the quality of being secluded from the presence or view of others; the condition of being concealed or hidden
probability - the quality of being probable; a probable event or the most probable event; a measure of how likely it is that some event will occur; a number expressing the ratio of favorable cases to the whole number of cases possible
probenecid - a uricosuric drug that reduces the level of uric acid in the blood; used to treat gout
proboscis - a long flexible snout as of an elephant; the human nose (especially when it is large)
procaine - a white crystalline powder (trade name Ethocaine) administered near nerves as a local anesthetic in dentistry and medicine
procarbazine - an antineoplastic drug used to treat Hodgkin's disease
processor - a business engaged in processing agricultural products and preparing them for market; someone who processes things (foods or photographs or applicants etc.); (computer science) the part of a computer (a microprocessor chip) that does most of the data processing
prochlorperazine - antipsychotic and antiemetic drug used to treat schizophrenia and to combat nausea and vomiting
proctitis - inflammation of the rectum; marked by bloody stools and a frequent urge to defecate; frequently associated with Crohn's disease or ulcerative colitis
proctoscope - an endoscope for examining the rectum
proctoscopy - visual examination of the rectum and the end of the colon by means of a proctoscope
progeria - a rare abnormality marked by premature aging (grey hair and wrinkled skin and stooped posture) in a child
progesterone - a steroid hormone (trade name Lipo-Lutin) produced in the ovary; prepares and maintains the uterus for pregnancy
progestin - any of a group of steroid hormones that have the effect of progesterone
prognosis - a prediction of the course of a disease; a prediction about how something (as the weather) will develop
prokaryote - a unicellular organism having cells lacking membrane-bound nuclei; bacteria are the prime example but also included are blue-green algae and actinomycetes and mycoplasma
prolactin - gonadotropic hormone secreted by the anterior pituitary; in females it stimulates growth of the mammary glands and lactation after parturition
proliferation - growth by the rapid multiplication of parts; a rapid increase in number (especially a rapid increase in the number of deadly weapons)
proline - an amino acid that is found in many proteins (especially collagen)
promethazine - antihistamine (trade name Phenergan) used to treat allergies; also an antiemetic used to treat motion sickness
prone - lying face downward; having a tendency (to); often used in combination
propane - colorless gas found in natural gas and petroleum; used as a fuel
propanol - a clear colorless volatile liquid (alcohol) used as a solvent and antiseptic
prophase - the first stage of mitosis; the first stage of meiosis
propoxyphene - a mildly narcotic analgesic drug (trade name Darvon) related to methadone but less addictive
proprioception - the ability to sense the position and location and orientation and movement of the body and its parts
propylene glycol - a sweet colorless, viscous, hygroscopic liquid used as an antifreeze and in brake fluid and also as a humectant in cosmetics and personal care items although it can be absorbed through the skin with harmful effects
propylthiouracil - a crystalline compound used as an antithyroid drug in the treatment of goiter
prosencephalon - the anterior portion of the brain; the part of the brain that develops from the anterior part of the neural tube
prostaglandin - a potent substance that acts like a hormone and is found in many bodily tissues (and especially in semen); produced in response to trauma and may affect blood pressure and metabolism and smooth muscle activity
prostate cancer - cancer of the prostate gland
prostate specific antigen - a protein manufactured exclusively by the prostate gland; PSA is produced for the ejaculate where it liquifies the semen and allows sperm cells to swim freely; elevated levels of PSA in blood serum are associated with benign prostatic hyperplasia and prostate cancer
prostate - relating to the prostate gland; a firm partly muscular chestnut sized gland in males at the neck of the urethra; produces a viscid secretion that is the fluid part of semen
prostatectomy - surgical removal of part or all of the prostate gland
prostatitis - inflammation of the prostate gland characterized by perineal pain and irregular urination and (if severe) chills and fever
prosthesis - corrective consisting of a replacement for a part of the body
protamine - a simple protein found in fish sperm; rich in arginine; simpler in composition than globulin or albumin; counteracts the anticoagulant effect of heparin
protease inhibitor - an antiviral drug used against HIV; interrupts HIV replication by binding and blocking HIV protease; often used in combination with other drugs
protein folding - the process whereby a protein molecule assumes its intricate three-dimensional shape
protein - any of a large group of nitrogenous organic compounds that are essential constituents of living cells; consist of polymers of amino acids; essential in the diet of animals for growth and for repair of tissues; can be obtained from meat and eggs and milk and legumes
proteinuria - the presence of excessive protein (chiefly albumin but also globulin) in the urine; usually a symptom of kidney disorder
proteolysis - the hydrolysis of proteins into peptides and amino acids by cleavage of their peptide bonds
proteome - the full complement of proteins produced by a particular genome
proteomics - the branch of genetics that studies the full set of proteins encoded by a genome
proteus - type genus of the Proteidae; (Greek mythology) a prophetic god who served Poseidon; was capable of changing his shape at will
prothrombin - a protein in blood plasma that is the inactive precursor of thrombin
protista - eukaryotic one-celled living organisms distinct from multicellular plants and animals: protozoa, slime molds, and eukaryotic algae
proto-oncogene - a normal gene that has the potential to become an oncogene
protoplasm - the substance of a living cell (including cytoplasm and nucleus)
protoplast - a biological unit consisting of a nucleus and the body of cytoplasm with which it interacts
protozoa - in some classifications considered a superphylum or a subkingdom; comprises flagellates; ciliates; sporozoans; amoebas; foraminifers
protozoal infection - any infection caused by a protozoan
provenance - where something originated or was nurtured in its early existence
proximal - situated nearest to point of attachment or origin
pseudoephedrine - poisonous crystalline alkaloid occurring with ephedrine and isomorphic with it
pseudohermaphroditism - congenital condition in which a person has external genitalia of one sex and internal sex organs of the other sex
pseudomonas - type genus of the family Pseudomonodaceae
psilocybin - a hallucinogenic compound obtained from a mushroom
psittacosis - an atypical pneumonia caused by a rickettsia microorganism and transmitted to humans from infected birds; infectious disease of birds
psoriasis - a chronic skin disease characterized by dry red patches covered with scales; occurs especially on the scalp and ears and genitalia and the skin over bony prominences
psoriatic arthritis - a form of rheumatoid arthritis usually affecting fingers and toes and associated with psoriasis
psychiatrist - a physician who specializes in psychiatry
psychiatry - the branch of medicine dealing with the diagnosis and treatment of mental disorders
psychodidae - very small two-winged flies with hairy wings that develop in moss and damp vegetable matter: sand flies
psychology - the science of mental life
psychometrics - any branch of psychology concerned with psychological measurements
psychopathology - the branch of medicine dealing with the diagnosis and treatment of mental disorders; the branch of psychology concerned with abnormal behavior
psychopharmacology - the study of drugs that affect the mind
psychophysics - the branch of psychology concerned with quantitative relations between physical stimuli and their psychological effects
psychophysiology - the branch of psychology that is concerned with the physiological bases of psychological processes
psychosexual development - (psychoanalysis) the process during which personality and sexual behavior mature through a series of stages: first oral stage and then anal stage and then phallic stage and then latency stage and finally genital stage
psychosurgery - brain surgery on human patients intended to relieve severe and otherwise intractable mental or behavioral problems
psychotherapy - the treatment of mental or emotional problems by psychological means; the branch of psychiatry concerned with psychological methods
pterygium - either of two thickened triangular layers of conjunctiva extending from the nasal edge of the eye to the cornea; it arises from irritation of the pinguecula
ptosis - drooping of the upper eyelid caused by muscle paralysis and weakness
puberty - the time of life when sex glands become functional
publication - the business of issuing printed matter for sale or distribution; the communication of something to the public; making information generally known; a copy of a printed work offered for distribution; the act of issuing printed materials
pulmonary artery - one of two arteries (branches of the pulmonary trunk) that carry venous blood from the heart to the lungs
pulmonary circulation - circulation of blood between the heart and the lungs
pulmonary embolism - blockage of the pulmonary artery by foreign matter or by a blood clot
pulmonary emphysema - an abnormal condition of the lungs marked by decreased respiratory function; associated with smoking or chronic bronchitis or old age
pulmonary stenosis - abnormal narrowing of the opening into the pulmonary artery from the right ventricle
pulmonary trunk - the artery that carries venous blood from the right ventricle of the heart and divides into the right and left pulmonary arteries
pulmonary valve - a semilunar valve between the right ventricle and the pulmonary artery; prevents blood from flowing from the artery back into the heart
pulmonary vein - any of four veins that carry arterial blood from the lungs to the left atrium of the heart
punishment - the act of punishing
pupil - contractile aperture in the iris of the eye; a young person attending school (up through senior high school); a learner who is enrolled in an educational institution
purine - a colorless crystalline organic base containing nitrogen; the parent compound of various biologically important substances; any of several bases that are derivatives of purine
purkinje cell - a large densely branching neuron that is the characteristic cell of the cerebellar cortex
purpura - any of several blood diseases causing subcutaneous bleeding
pus - a fluid product of inflammation; the tenth month of the Hindu calendar
pustule - a small inflamed elevation of skin containing pus; a blister filled with pus
putamen - the outer reddish part of the lenticular nucleus
putrescine - a colorless crystalline ptomaine with a foul odor that is produced in decaying animal matter
pycnodysostosis - a form of dwarfism accompanied by fragile bones and bad teeth
pyelitis - inflammation of the renal pelvis
pyelonephritis - inflammation of the kidney and its pelvis caused by bacterial infection
pyloric stenosis - narrowing of the pyloric sphincter that blocks the passage of food from the stomach into the duodenum
pylorus - a small circular opening between the stomach and the duodenum
pyramidal tract - any of the important motor nerves on each side of the central nervous system that run from the sensorimotor areas of the cortex through the brainstem to motor neurons of the cranial nerve nuclei and the ventral horn of the spinal cord
pyrene - the small hard nutlet of a drupe or drupelet; the seed and the hard endocarp that surrounds it; a pale yellow crystalline hydrocarbon C16H10 extracted from coal tar
pyridine - a toxic colorless flammable liquid organic base with a disagreeable odor; usually derived from coal
pyridoxine - a B vitamin that is essential for metabolism of amino acids and starch
pyrogen - any substance that can cause a rise in body temperature; any substance characterized by its great flammability
pyuria - presence of white blood cells in the urine; symptom of urinary tract infection
q fever - an acute disease resembling influenza
quadriceps femoris - a muscle of the thigh that extends the leg
quadriplegia - paralysis of both arms and both legs
quality control - maintenance of standards of quality of manufactured goods
quality of life - your personal satisfaction (or dissatisfaction) with the cultural or intellectual conditions under which you live (as distinct from material comfort)
quarantine - isolation to prevent the spread of infectious disease; enforced isolation of patients suffering from a contagious disease in order to prevent the spread of disease; verb place into enforced isolation, as for medical reasons
questionnaire - a form containing a set of questions; submitted to people to gain statistical information
quinidine - cardiac drug (trade names Quinidex and Quinora) used to treat certain heart arrhythmias
quinine - a bitter alkaloid extracted from chinchona bark; used in malaria therapy
rabies - an acute viral disease of the nervous system of warm-blooded animals (usually transmitted by the bite of a rabid animal); rabies is fatal if the virus reaches the brain
radial nerve - largest branch of the brachial plexus; extends down the humerus to the lateral epicondyle where it divides into one branch that goes to the skin on the back of the hand and another that goes to the underlying extensor muscles
radiation field - a field that represents the energy lost from the radiator to space
radiation therapy - (medicine) the treatment of disease (especially cancer) by exposure to a radioactive substance
radical hysterectomy - surgical removal of the uterus and the ovaries and oviducts and cervix and related lymph nodes
radical mastectomy - removal of a breast and the underlying muscles (pectoralis major and pectoralis minor) and lymph nodes in the adjacent armpit
radiculitis - inflammation of the radicle of a nerve
radiobiology - the branch of biology that studies the effects of radiation on living organisms
radiochemistry - the chemistry of radioactive substances
radioimmunoassay - immunoassay of a substance that has been radioactively labeled
radioisotope - a radioactive isotope of an element; produced either naturally or artificially
radiologist - a medical specialist who uses radioactive substances and X-rays in the treatment of disease
radiology - the branch of medical science dealing with the medical use of X-rays or other penetrating radiation; (radiology) examination of the inner structure of opaque objects using X rays or other penetrating radiation
radiopharmaceutical - pharmaceutical consisting of a radioactive compound used in radiation therapy
radium - an intensely radioactive metallic element that occurs in minute amounts in uranium ores
radon - a radioactive gaseous element formed by the disintegration of radium; the heaviest of the inert gasses; occurs naturally (especially in areas over granite) and is considered a hazard to health
raffinose - a trisaccharide that occurs in sugar beets and cotton seeds and certain cereals
rale - a rapid series of short loud sounds (as might be heard with a stethoscope in some types of respiratory disorders)
randomization - a deliberately haphazard arrangement of observations so as to simulate chance
ranitidine - a histamine blocker and antacid (trade name Zantac) used to treat peptic ulcers and gastritis and esophageal reflux
ratio - the relative magnitudes of two quantities (usually expressed as a quotient)
rationalization - the organization of a business according to scientific principles of management in order to increase efficiency; (mathematics) the simplification of an expression or equation by eliminating radicals without changing the value of the expression or the roots of the equation; the cognitive process of making something seem consistent with or based on reason; (psychiatry) a defense mechanism by which your true motivation is concealed by explaining your actions and feelings in a way that is not threatening; systematic organization; the act of organizing something according to a system or a rationale
reaction time - the time that elapses between a stimulus and the response to it
reaction - doing something in opposition to another way of doing it that you don't like; a bodily process occurring due to the effect of some foregoing stimulus or agent; an idea evoked by some experience; extreme conservatism in political or social matters; a response that reveals a person's feelings or attitude; (mechanics) the equal and opposite force that is produced when any force is applied to a body; (chemistry) a process in which one or more substances are changed into others
reagent - a chemical agent for use in chemical reactions
receive - verb convert into sounds or pictures; receive a specified treatment (abstract); regard favorably or with disapproval; accept as true or valid; partake of the Holy Eucharist sacrament; express willingness to have in one's home or environs; get something; come into possession of; have or give a reception; bid welcome to; greet upon arrival; register (perceptual input); go through (mental or physical states or experiences); receive as a retribution or punishment; experience as a reaction
receptor - a cellular structure that is postulated to exist in order to mediate between a chemical agent that acts on nervous tissue and the physiological response; an organ having nerve endings (in the skin or viscera or eye or ear or nose or mouth) that respond to stimulation
recombinant dna - genetically engineered DNA made by recombining fragments of DNA from different organisms
rectal - of or involving the rectum
rectocele - protrusion or herniation of the rectum into the vagina; can occur if pelvic muscles are weakened by childbirth
rectum - the terminal section of the alimentary canal; from the sigmoid flexure to the anus
reducing diet - a diet designed to help you lose weight (especially fat)
reduviidae - assassin bugs
referral - the act of referring (as forwarding an applicant for employment or referring a matter to an appropriate agency); a recommendation to consult the (professional) person referred to
reflex epilepsy - a form of epilepsy in which attacks are induced by peripheral stimulation
reflex - without volition or conscious control; an automatic instinctive unlearned reaction to a stimulus
refractometer - measuring instrument for measuring the refractive index of a substance
refractory anemia - any of various anemic conditions that are not successfully treated by any means other than blood transfusions (and that are not associated with another primary disease)
refractory - temporarily unresponsive or not fully responsive to nervous or sexual stimuli; not responding to treatment; stubbornly resistant to authority or control; lining consisting of material with a high melting point; used to line the inside walls of a furnace
regeneration - the activity of spiritual or physical renewal; (biology) growth anew of lost tissue or destroyed parts or organs; forming again (especially with improvements or removal of defects); renewing and reconstituting; feedback in phase with (augmenting) the input
regional - related or limited to a particular region; characteristic of a region
regulation - prescribed by or according to regulation; the act of controlling or directing according to rule; the act of bringing to uniformity; making regular; an authoritative rule; (embryology) the ability of an early embryo to continue normal development after its structure has been somehow damaged or altered; the state of being controlled or governed; a principle or condition that customarily governs behavior
regulatory authority - a governmental agency that regulates businesses in the public interest
regulatory gene - a gene that produces a repressor substance that inhibits an operator gene
regurgitation - recall after rote memorization; backflow of blood through a defective heart valve; the reflex act of ejecting the contents of the stomach through the mouth
rehabilitation - the restoration of someone to a useful place in society; the treatment of physical disabilities by massage and electrotherapy and exercises; vindication of a person's character and the re-establishment of that person's reputation; the conversion of wasteland into land suitable for use of habitation or cultivation
reiter's syndrome - an inflammatory syndrome (etiology unknown) predominantly in males; characterized by arthritis and conjunctivitis and urethritis
relaxation - a method of solving simultaneous equations by guessing a solution and then reducing the errors that result by successive approximations until all the errors are less than some specified amount; an occurrence of control or strength weakening; (physics) the exponential return of a system to equilibrium after a disturbance; (physiology) the gradual lengthening of inactive muscle or muscle fibers; the act of making less strict; freedom from activity (work or strain or responsibility); a feeling of refreshing tranquility and an absence of tension or worry
relaxin - hormone secreted by the corpus luteum during the last days of pregnancy; relaxes the pelvic ligaments and prepares the uterus for labor
religion - a strong belief in a supernatural power or powers that control human destiny; an institution to express belief in a divine power
rem sleep - a recurring sleep state during which dreaming occurs; a state of rapidly shifting eye movements during sleep
remission - (law) the act of remitting (especially the referral of a law case to another court); an abatement in intensity or degree (as in the manifestations of a disease); the act of absolving or remitting; formal redemption as proced by a priest in the sacrament of penance; a payment of money sent to a person in another place
renal artery - an artery originating from the abdominal aorta and supplying the kidneys and adrenal glands and ureters
renal colic - sharp pain in the lower back that radiates into the groin; associated with the passage of a renal calculus through the ureter
renal cortex - the cortex of the kidney containing the glomeruli and the convoluted tubules
renal failure - inability of the kidneys to excrete wastes and to help maintain the electrolyte balance
renal insufficiency - insufficient excretion of wastes by the kidneys
renal pelvis - a structure shaped like a funnel in the outlet of the kidney into which urine is discharged before passing into the ureter
renal vein - veins that accompany renal arteries; open into the vena cava at the level of the 2nd lumbar vertebra
renin - a proteolytic enzyme secreted by the kidneys; catalyzes the formation of angiotensin and thus affects blood pressure
reoviridae - a family of arboviruses carried by arthropods
repression - the act of repressing; control by holding down; (psychiatry) the classical defense mechanism that protects you from impulses or ideas that would cause anxiety by preventing them from becoming conscious; a state of forcible subjugation
reproduction - the sexual activity of conceiving and bearing offspring; the act of making copies; recall that is hypothesized to work by storing the original stimulus input and reproducing it during recall; the process of generating offspring; copy that is not the original; something that has been copied
reproductive system - organs and tissues involved in the production and maturation of gametes and in their union and subsequent development as offspring
reserpine - antihypertensive consisting of an alkaloid extracted from the plant Rauwolfia serpentina (trade names Raudixin or Rau-Sed or Sandril or Serpasil)
resin - any of a class of solid or semisolid viscous substances obtained either as exudations from certain plants or prepared by polymerization of simple molecules
resorption - the organic process in which the substance of some differentiated structure that has been produced by the body undergoes lysis and assimilation
respiration - the metabolic processes whereby certain organisms obtain energy from organic molecules; processes that take place in the cells and tissues during which energy is released and carbon dioxide is produced and absorbed by the blood to be transported to the lungs; a single complete act of breathing in and out; the bodily process of inhalation and exhalation; the process of taking in oxygen from inhaled air and releasing carbon dioxide by exhalation
respiratory acidosis - acidosis resulting from reduced gas exchange in the lungs (as in emphysema or pneumonia); excess carbon dioxide combines with water to form carbonic acid which increases the acidity of the blood
respiratory alkalosis - alkalosis resulting from increased gas exchange in the lungs (as in hyperventilation associated with extreme anxiety or aspirin intoxication or metabolic acidosis)
respiratory disorder - a disease affecting the respiratory system
respiratory infection - any infection of the respiratory tract
respiratory rate - the rate at which a person inhales and exhales; usually measured to obtain a quick evaluation of a person's health
respiratory system - the system for taking in oxygen and giving off carbon dioxide; in terrestrial animals this is accomplished by breathing
restless legs syndrome - feeling of uneasiness and restlessness in the legs after going to bed (sometimes causing insomnia); may be relieved temporarily by walking or moving the legs
restlessness - inability to rest or relax or be still; the quality of being ceaselessly moving or active; a lack of patience; irritation with anything that causes delay; a feeling of agitation expressed in continual motion
resuscitation - the act of reviving a person and returning them to consciousness
reticular formation - a complex neural network in the central core of the brainstem; monitors the state of the body and functions in such processes as arousal and sleep and attention and muscle tone
reticulocyte - an immature red blood cell containing a network of filaments or granules
reticuloendothelial system - a widely distributed system consisting of all the cells able to ingest bacteria or colloidal particles etc, except for certain white blood cells
reticulum - the second compartment of the stomach of a ruminant; any fine network (especially one in the body composed of cells or blood vessels); a small constellation in the southern hemisphere near Dorado and Hydrus
retina - the light-sensitive membrane covering the back wall of the eyeball; it is continuous with the optic nerve
retinal cone - visual receptor cell sensitive to color
retinal detachment - visual impairment resulting from the retina becoming separated from the choroid in the back of the eye; treated by photocoagulation
retinitis - inflammation of the retina
retinoblastoma - malignant ocular tumor of retinal cells; usually occurs before the third year of life; composed of primitive small round retinal cells
retirement - withdrawal for prayer and study and meditation; withdrawal from your position or occupation; the state of being retired from one's business or occupation
retractor - surgical instrument that holds back the edges of a surgical incision
retrograde amnesia - loss of memory for events immediately preceding a trauma
reye's syndrome - acquired brain disorder following acute viral infections (especially influenza or chicken pox) in young children
rhabdomyoma - benign rumor of striated muscle
rhabdomyosarcoma - a highly malignant neoplasm derived from striated muscle
rhabdoviridae - a family of arborviruses carried by arthropods
rheumatic fever - a severe disease chiefly of children and characterized by painful inflammation of the joints and frequently damage to the heart valves
rheumatic heart disease - heart disease caused by recurrent episodes of rheumatic fever; characterized by changes in the myocardium or scarring of the heart valves that reduce the power of the heart to pump blood
rheumatism - any painful disorder of the joints or muscles or connective tissues; a chronic autoimmune disease with inflammation of the joints and marked deformities; something (possibly a virus) triggers an attack on the synovium by the immune system, which releases cytokines that stimulate an inflammatory reaction that can lead to the destruction of all components of the joint
rheumatoid arthritis - a chronic autoimmune disease with inflammation of the joints and marked deformities; something (possibly a virus) triggers an attack on the synovium by the immune system, which releases cytokines that stimulate an inflammatory reaction that can lead to the destruction of all components of the joint
rheumatoid factor - autoantibody that is usually present in the serum of people with rheumatoid arthritis
rhinitis - an inflammation of the mucous membrane lining the nose (usually associated with nasal discharge)
rhinophyma - enlargement of the nose with dilation of follicles and redness and prominent vascularity of the skin; often associated with excessive consumption of alcohol
rhinoplasty - cosmetic surgery to improve the appearance of your nose
rhinorrhea - persistent watery mucus discharge from the nose (as in the common cold)
rhinoscopy - examination of the nasal passages (either through the anterior nares or with a rhinoscope through the nasopharynx)
rhinovirus - any of a group of picornaviruses that are responsible for many upper respiratory infections
rhizobiaceae - a small family of rod-shaped bacteria
rhizobium - the type genus of Rhizobiaceae; usually occur in the root nodules of legumes; can fix atmospheric oxygen
rhizopus - any of various rot causing fungi of the genus Rhizopus
rhodium - a white hard metallic element that is one of the platinum group and is found in platinum ores; used in alloys with platinum
rhodopsin - a red photopigment in the retinal rods of vertebrates; dissociates into retinene by light
rhombencephalon - the posterior portion of the brain including cerebellum and brainstem
rib - support resembling the rib of an animal; a projecting molding on the underside of a vault or ceiling; may be ornamental or structural; a riblike supporting or strengthening part of an animal or plant; any of the 12 pairs of curved arches of bone extending from the spine to or toward the sternum in humans (and similar bones in most vertebrates); a teasing remark; cut of meat including one or more ribs; verb form vertical ribs by knitting; subject to laughter or ridicule
ribavirin - an inhaled antiviral agent (trade name Virazole) that may be used to treat serious virus infections
riboflavin - a B vitamin that prevents skin lesions and weight loss
ribonuclease - a transferase that catalyzes the hydrolysis of ribonucleic acid
ribonucleic acid - (biochemistry) a long linear polymer of nucleotides found in the nucleus but mainly in the cytoplasm of a cell where it is associated with microsomes; it transmits genetic information from DNA to the cytoplasm and controls certain chemical processes in the cell
ribose - a pentose sugar important as a component of ribonucleic acid
ribosome - an organelle in the cytoplasm of a living cell; they attach to mRNA and move down it one codon at a time and then stop until tRNA brings the required amino acid; when it reaches a stop codon it falls apart and releases the completed protein molecule for use by the cell
ricin - a toxic protein extracted from castor beans; used as a chemical reagent; can be used as a bioweapon
rickets - childhood disease caused by deficiency of vitamin D and sunlight associated with impaired metabolism of calcium and phosphorus
rickettsia - any of a group of very small rod-shaped bacteria that live in biting arthropods (as ticks and mites) and cause disease in vertebrate hosts; they cause typhus and other febrile diseases in human beings
rickettsiaceae - microorganism resembling bacteria inhabiting arthropod tissues but capable of causing disease in vertebrates
rifampin - an antibacterial drug (trade names Rifadin and Rimactane) used to treat tuberculosis
right atrium - the right upper chamber of the heart that receives blood from the venae cavae and coronary sinus
right ventricle - the chamber on the right side of the heart that receives venous blood from the right atrium and pumps it into the pulmonary trunk
risk - a venture undertaken without regard to possible loss or injury; the probability of being exposed to an infectious agent; the probability of becoming infected given that exposure to an infectious agent has occurred; a source of danger; a possibility of incurring loss or misfortune; verb expose to a chance of loss or damage; take a risk in the hope of a favorable outcome
ritonavir - a protease inhibitor (trade name Norvir) used in treating HIV
ritual - of or relating to or employed in social rites or rituals; of or relating to or characteristic of religious rituals; stereotyped behavior; any customary observance or practice; the prescribed procedure for conducting religious ceremonies
roentgen - German physicist who discovered x-rays and developed roentgenography (1845-1923); a unit of radiation exposure; the dose of ionizing radiation that will produce 1 electrostatic unit of electricity in 1 cc of dry air
rofecoxib - a Cox-2 inhibitor (trade name Vioxx) that relieves pain without harming the digestive tract; voluntarily withdrawn from the market in 2004
rooting reflex - reflex consisting of head-turning and sucking movements elicited in a normal infant by gently stroking the side of the mouth or cheek
rosacea - a skin disease of adults (more often women) in which blood vessels of the face enlarge resulting in a flushed appearance
rotation - the act of rotating as if on an axis; a planned recurrent sequence (of crops or personnel etc.); a single complete turn (axial or orbital); (mathematics) a transformation in which the coordinate axes are rotated by a fixed angle about the origin
rotator cuff - a supporting structure of the shoulder consisting of the muscles and tendons that attach the arm to the shoulder joint and enable the arm to move
rotavirus - the reovirus causing infant enteritis
rotifera - a phylum including: rotifers
rubber - returned for lack of funds; an elastic material obtained from the latex sap of trees (especially trees of the genera Hevea and Ficus) that can be vulcanized and finished into a variety of products; any of various synthetic elastic materials whose properties resemble natural rubber; a waterproof overshoe that protects shoes from water or snow; contraceptive device consisting of a sheath of thin rubber or latex that is worn over the penis during intercourse; an eraser made of rubber (or of a synthetic material with properties similar to rubber); commonly mounted at one end of a pencil; verb coat or impregnate with rubber
rubella - a contagious viral disease that is a milder form of measles lasting three or four days; can be damaging to a fetus during the first trimester
rubidium - a soft silvery metallic element of the alkali metal group; burns in air and reacts violently in water; occurs in carnallite and lepidolite and pollucite
rumen - the first compartment of the stomach of a ruminant; here food is collected and returned to the mouth as cud for chewing
rumination - regurgitation of small amounts of food; seen in some infants after feeding; (of ruminants) chewing (the cud); a calm lengthy intent consideration
rupture - the act of making a sudden noisy break; a personal or social separation (as between opposing factions); state of being torn or burst open; verb separate or cause to separate abruptly
ruthenium - a rare polyvalent metallic element of the platinum group; it is found associated with platinum
saccade - a rapid, jerky movement of the eyes between positions of rest; an abrupt spasmodic movement
saccharomyces cerevisiae - used as a leaven in baking and brewing
saccharomyces - single-celled yeasts that reproduce asexually by budding; used to ferment carbohydrates
sacrum - wedge-shaped bone consisting of five fused vertebrae forming the posterior part of the pelvis; its base connects with the lowest lumbar vertebra and its tip with the coccyx
safflower oil - oil from seeds of the safflower plant; oil from safflower seeds used as food as well as in medicines and paints
salicylic acid - a white crystalline substance with a bitter aftertaste; used as a fungicide or in making aspirin or dyes or perfumes
saline - containing salt; an isotonic solution of sodium chloride and distilled water
saliva - a clear liquid secreted into the mouth by the salivary glands and mucous glands of the mouth; moistens the mouth and starts the digestion of starches
salivary gland - any of three pairs of glands in the mouth and digestive system that secrete saliva for digestion
salmonella typhi - a form of salmonella that causes typhoid fever
salmonella typhimurium - a form of salmonella that causes food poisoning in humans
salmonella - rod-shaped Gram-negative enterobacteria; cause typhoid fever and food poisoning; can be used as a bioweapon
salpingectomy - surgical removal of one or both Fallopian tubes
salpingitis - inflammation of a Fallopian tube (usually the result of infection spreading from the vagina or uterus) or of a Eustachian tube
salt - (of speech) painful or bitter; one of the four basic taste sensations; like the taste of sea water; the taste experience when common salt is taken into the mouth; white crystalline form of especially sodium chloride used to season and preserve food; a compound formed by replacing hydrogen in an acid by a metal (or a radical that acts like a metal); negotiations between the United States and the Union of Soviet Socialist Republics opened in 1969 in Helsinki designed to limit both countries' stock of nuclear weapons; verb preserve with salt; add zest or liveliness to; sprinkle as if with salt; add salt to
saphenous vein - either of two chief superficial veins of the leg that drain blood from the foot
saquinavir - a weak protease inhibitor (trade name Invirase) used in treating HIV
sarcocystis - chief genus of the order Sarcosporidia
sarcoidosis - a chronic disease of unknown cause marked by the formation of nodules in the lungs and liver and lymph glands and salivary glands
sarcolemma - an extensible membrane enclosing the contractile substance of a muscle fiber
sarcoma - a usually malignant tumor arising from connective tissue (bone or muscle etc.); one of the four major types of cancer
sarcomere - one of the segments into which a myofibril is divided
sarcoplasm - the cytoplasm of a striated muscle fiber
sarcosine - a sweetish crystalline amino acid
satiation - the act of achieving full gratification; the state of being satisfactorily full and unable to take on more
satisfaction - act of fulfilling a desire or need or appetite; the contentment you feel when you have done something right; compensation for a wrong; state of being gratified; great satisfaction
saxitoxin - a powerful neurotoxin produced by certain dinoflagellates found in red tides; it can accumulate in mollusks that feed on the dinoflagellates and cause food poisoning to humans
scabies - a contagious skin infection caused by the itch mite; characterized by persistent itching and skin irritation
scalp - the skin that covers the top of the head; verb remove the scalp of; sell illegally, as on the black market
scalpel - a thin straight surgical knife used in dissection and surgery
scaphoid bone - the largest wrist bone on the thumb side
scapula - either of two flat triangular bones one on each side of the shoulder in human beings
scar - a mark left (usually on the skin) by the healing of injured tissue; an indication of damage; verb mark with a scar
scarlet fever - an acute communicable disease (usually in children) characterized by fever and a red rash
schistosoma - type genus of the family Schistosomatidae: blood flukes
schistosomiasis - an infestation with or a resulting infection caused by a parasite of the genus Schistosoma; common in the tropics and Far East; symptoms depend on the part of the body infected
schizophrenia - any of several psychotic disorders characterized by distortions of reality and disturbances of thought and language and withdrawal from social contact
school - a building where young people receive education; the process of being formally educated at a school; a large group of fish; a body of creative artists or writers or thinkers linked by a similar style or by similar teachers; an educational institution; an educational institution's faculty and students; the period of instruction in a school; the time period when schools is in session; verb swim in or form a large group of fish; educate in or as if in a school; train to be discriminative in taste or judgment
schwann cell - any cell that covers the nerve fibers in the peripheral nervous system and forms the myelin sheath
sciatic nerve - arises from the sacral plexus and passes about halfway down the thigh where it divides into the common peroneal and tibial nerves
sciatica - neuralgia along the sciatic nerve
scintillation counter - counter tube in which light flashes when exposed to ionizing radiation
sclera - whitish fibrous membrane (albuginea) that with the cornea forms the outer covering of the eyeball
scleredema - a skin disease marked by hard edema of the tissue usually beginning in the face
scleritis - inflammation of the sclera
scleroderma - genus of poisonous fungi having hard-skinned fruiting bodies: false truffles; an autoimmune disease that affects the blood vessels and connective tissue; fibrous connective tissue is deposited in the skin
sclerosis - any pathological hardening or thickening of tissue
scoliosis - an abnormal lateral curve to the vertebral column
scotoma - an isolated area of diminished vision within the visual field
scrapie - a fatal disease of sheep characterized by chronic itching and loss of muscular control and progressive degeneration of the central nervous system
scrotum - the external pouch that contains the testes
scurvy - of the most contemptible kind; a condition caused by deficiency of ascorbic acid (vitamin C)
season - one of the natural periods into which the year is divided by the equinoxes and solstices or atmospheric conditions; a recurrent time marked by major holidays; a period of the year marked by special events or activities in some field; verb make fit; lend flavor to; make more temperate, acceptable, or suitable by adding something else; moderate
sebaceous gland - a cutaneous gland that secretes sebum (usually into a hair follicle) for lubricating hair and skin
seborrheic dermatitis - a chronic skin disease associated with seborrhea and greasy scales on the scalp or eyelids or other parts of the skin
seborrheic keratosis - a skin condition characterized by circumscribed wartlike lesions that can be itchy and covered with a greasy crust
sebum - the oily secretion of the sebaceous glands; with perspiration it moistens and protects the skin
secondary amenorrhea - cessation of menstruation in a woman who had previously menstruated
secondary hypertension - hypertension that is secondary to another disease
secretin - peptic hormone produced by the mucous lining of the small intestine; can stimulate secretion by the pancreas and liver
secretion - a functionally specialized substance (especially one that is not a waste) released from a gland or cell; the organic process of synthesizing and releasing some substance
seizure - the taking possession of something by legal process; a sudden occurrence (or recurrence) of a disease; the act of forcibly dispossessing an owner of property; the act of taking of a person by force
selenium - a toxic nonmetallic element related to sulfur and tellurium; occurs in several allotropic forms; a stable grey metallike allotrope conducts electricity better in the light than in the dark and is used in photocells; occurs in sulfide ores (as pyrite)
self-examination - the contemplation of your own thoughts and desires and conduct
self-stimulation - manual stimulation of your own genital organ for sexual pleasure
semantics - the study of language meaning
semen - the thick white fluid containing spermatozoa that is ejaculated by the male genital tract
semilunar bone - one of the eight small wrist bones
seminal fluid - the thick white fluid containing spermatozoa that is ejaculated by the male genital tract
seminal vesicle - either of a pair of glands located on either side of the male urinary bladder that open into the vas deferens and that secrete many components of semen during ejaculation
seminoma - malignant tumor of the testis; usually occurring in older men
senile dementia - dementia of the aged; results from degeneration of the brain in the absence of cerebrovascular disease
sense organ - an organ having nerve endings (in the skin or viscera or eye or ear or nose or mouth) that respond to stimulation
sensorineural hearing loss - hearing loss due to failure of the auditory nerve
sensory deprivation - a form of psychological torture inflicted by depriving the victim of all sensory input
sensory nerve - a nerve that passes impulses from receptors toward or to the central nervous system
sepsis - the presence of pus-forming bacteria or their toxins in the blood or tissues
septate - of or relating to a septum
septicemia - invasion of the bloodstream by virulent microorganisms from a focus of infection
sequential - in regular succession without gaps
serine - a sweetish crystalline amino acid involved in the synthesis by the body of cysteine
serotonin - a neurotransmitter involved in e.g. sleep and depression and memory
serous membrane - a thin membrane lining the closed cavities of the body; has two layers with a space between that is filled with serous fluid
serous - of or producing or containing serum
serratia marcescens - the type species of the genus Serratia; a species found in water and soil and milk and foods and insects; can cause infections of the endocardium and blood and wounds and urinary tract and respiratory tract; has been tested as a bioweapon
serratia - a genus of motile peritrichous bacteria that contain small Gram-negative rod
sertoli cell - elongated cells found in the seminiferous tubules of the testis; apparently they nourish the spermatids
sertraline - a selective-serotonin reuptake inhibitor commonly prescribed as an antidepressant (trade name Zoloft)
serum albumin - albumin occurring in blood serum; serves to maintain the somatic pressure of the blood
serum globulin - globulins occurring in blood serum and containing most of the antibodies of the blood
serum sickness - a delayed allergic reaction to the injection of an antiserum caused by an antibody reaction to an antigen in the donor serum
serum - watery fluid of the blood that resembles plasma but contains fibrinogen
sesame oil - oil obtained from sesame seeds
severe - very bad in degree or extent; unsparing and uncompromising in discipline or judgment; intensely or extremely bad or unpleasant in degree or quality; causing fear or anxiety by threatening great harm; severely simple; very strong or vigorous
sex characteristic - those characteristics (both anatomical and psychological) that are strongly associated with one sex relative to the other
sex chromatin - chromatin found only in female cells
sex chromosome - (genetics) a chromosome that determines the sex of an individual
sex offense - a statutory offense that provides that it is a crime to knowingly cause another person to engage in an unwanted sexual act by force or threat
sex - the properties that distinguish organisms on the basis of their reproductive roles; all of the feelings resulting from the urge to gratify sexual impulses; either of the two categories (male or female) into which most organisms are divided; activities associated with sexual intercourse; verb tell the sex (of young chickens); stimulate sexually
sexuality - the properties that distinguish organisms on the basis of their reproductive roles
sexually transmitted disease - a communicable infection transmitted by sexual intercourse or genital contact
shame - a painful emotion resulting from an awareness of inadequacy or guilt; a state of dishonor; an unfortunate development; verb surpass or beat by a wide margin; cause to be ashamed; compel through a sense of shame; bring shame or dishonor upon
shampoo - the act of washing your hair with shampoo; cleansing agent consisting of soaps or detergents used for washing the hair; verb use shampoo on (hair)
shigella - rod-shaped Gram-negative enterobacteria; some are pathogenic for warm-blooded animals; can be used as a bioweapon
shingles - eruptions along a nerve path often accompanied by severe neuralgia
shivering - vibrating slightly and irregularly; as e.g. with fear or cold or like the leaves of an aspen in a breeze; a sensation of cold that often marks the start of an infection and the development of a fever
shock - the violent interaction of individuals or groups entering into combat; an unpleasant or disappointing surprise; an instance of agitation of the earth's crust; a bushy thick mass (especially hair); a pile of sheaves of grain set on end in a field to dry; stalks of Indian corn set up in a field; (pathology) bodily collapse or near collapse caused by inadequate oxygen delivery to the cells; characterized by reduced cardiac output and rapid heartbeat and circulatory insufficiency and pallor; a reflex response to the passage of electric current through the body; a mechanical damper; absorbs energy of sudden impulses; the feeling of distress and disbelief that you have when something bad happens accidentally; verb subject to electrical shocks; collect or gather into shocks; collide violently; strike with horror or terror; surprise greatly; knock someone's socks off; strike with disgust or revulsion; inflict a trauma upon
shoulder joint - a ball-and-socket joint between the head of the humerus and a cavity of the scapula
shoulder - narrow edge of land (usually unpaved) along the side of a road; the part of the body between the neck and the upper arm; a ball-and-socket joint between the head of the humerus and a cavity of the scapula; a cut of beef from the shoulder of the animal; verb push with the shoulders; carry a burden, either real or metaphoric; lift onto one's shoulders
sialadenitis - inflammation of the salivary glands
sibling - a person's brother or sister
sideroblastic anemia - refractory anemia characterized by sideroblasts in the bone marrow
sigmoid colon - the s-shaped curve between the descending colon and the rectum
sigmoidoscope - an endoscope (a flexible fiberoptic probe) for examining the sigmoid colon
sigmoidoscopy - visual examination (with a sigmoidoscope) of the lower third of the colon in a search for polyps
sildenafil citrate - virility drug (trade name Viagra) used to treat erectile dysfunction in men
silicate - a salt or ester derived from silicic acid
silicon dioxide - a white or colorless vitreous insoluble solid (SiO2); various forms occur widely in the earth's crust as quartz or cristobalite or tridymite or lechartelierite
silicone - any of a large class of siloxanes that are unusually stable over a wide range of temperatures; used in lubricants and adhesives and coatings and synthetic rubber and electrical insulation
silicosis - a lung disease caused by inhaling particles of silica or quartz or slate
silver nitrate - a nitrate used in making photographic emulsions; also used in medicine as a cautery and as a topical antibacterial agent
silver - having the white lustrous sheen of silver; made from or largely consisting of silver; expressing yourself readily, clearly, effectively; of lustrous grey; covered with or tinged with the color of silver; coins made of silver; a soft white precious univalent metallic element having the highest electrical and thermal conductivity of any metal; occurs in argentite and in free form; used in coins and jewelry and tableware and photography; silverware eating utensils; a trophy made of silver (or having the appearance of silver) that is usually awarded for winning second place in a competition; a light shade of grey; verb turn silver; make silver in color; coat with a layer of silver or a silver amalgam
simple mastectomy - removal of a breast leaving the underlying muscles and the lymph nodes intact
simuliidae - blackflies and sand flies
simvastatin - an oral lipid-lowering medicine (trade name Zocor) administered to reduce blood cholesterol levels; recommended after heart attacks
sinus - any of various air-filled cavities especially in the bones of the skull; a wide channel containing blood; does not have the coating of an ordinary blood vessel; an abnormal passage leading from a suppurating cavity to the body surface
sinusitis - inflammation of one of the paranasal sinuses
skeletal system - the hard structure (bones and cartilages) that provides a frame for the body of an animal
skeleton - the internal supporting structure that gives an artifact its shape; a scandal that is kept secret; something reduced to its minimal form; the hard structure (bones and cartilages) that provides a frame for the body of an animal
skin - an outer surface (usually thin); a bag serving as a container for liquids; it is made from the hide of an animal; a natural protective body covering and site of the sense of touch; a person's skin regarded as their life; the tissue forming the hard outer layer (of e.g. a fruit); body covering of a living animal; the rind of a fruit or vegetable; verb strip the skin off; bruise, cut, or injure the skin or the surface of; remove the bark of a tree; climb awkwardly, as if by scrambling
skull - the bony skeleton of the head of vertebrates
sleep apnea - apnea that occurs during sleep
sleep deprivation - a form of psychological torture inflicted by depriving the victim of sleep
sleep - a natural and periodic state of rest during which consciousness of the world is suspended; a torpid state resembling deep sleep; a period of time spent sleeping; euphemisms for death (based on an analogy between lying in a bed and in a tomb); verb be asleep; be able to accommodate for sleeping
sleeplessness - a temporary state in which you are unable (or unwilling) to sleep
small intestine - the longest part of the alimentary canal; where digestion is completed
small - limited or below average in number or quantity or magnitude or extent; slight or limited; especially in degree or intensity or scope; have fine or very small constituent particles; made to seem smaller or less (especially in worth); limited in size or scope; (of a voice) faint; lowercase; not large but sufficient in size or amount; (of children and animals) young, immature; low or inferior in station or quality; on a small scale; a garment size for a small person; the slender part of the back
smallpox virus - the virus that causes smallpox in humans; can be used as a bioweapon
smallpox - a highly contagious viral disease characterized by fever and weakness and skin eruption with pustules that form scabs that slough off leaving scars
smegma - a white secretion of the sebaceous glands of the foreskin
smoke - the act of smoking tobacco or other substances; something with no concrete substance; an indication of some hidden activity; a cloud of fine particles suspended in a gas; a hot vapor containing fine particles of carbon being produced by combustion; (baseball) a pitch thrown with maximum velocity; street names for marijuana; tobacco leaves that have been made into a cylinder; verb inhale and exhale smoke from cigarettes, cigars, pipes; emit a cloud of fine particles
smooth muscle cell - cells of the smooth muscles
smooth muscle - muscle tissue that does not appear striated under the microscope; has the form of thin layers or sheets; a muscle that contracts without conscious control and found in walls of internal organs such as stomach and intestine and bladder and blood vessels (excluding the heart)
sneeze - a symptom consisting of the involuntary expulsion of air from the nose; verb exhale spasmodically, as when an irritant entered one's nose
snoring - breathing during sleep with harsh noises caused by vibration of the uvula or soft palate; the act of snoring or producing a snoring sound
social psychology - the branch of psychology that studies persons and their relationships with others and with groups and with society as a whole
social work - any of various services designed to aid the poor and aged and to increase the welfare of children
socialization - the adoption of the behavior patterns of the surrounding culture; the act of meeting for social purposes; the action of establishing on a socialist basis
sodium bicarbonate - a white soluble compound (NaHCO3) used in effervescent drinks and in baking powders and as an antacid
sodium chloride - a white crystalline solid consisting mainly of sodium chloride (NaCl)
sodium fluoride - a colorless crystalline salt of sodium (NaF) used in fluoridation of water and to prevent tooth decay
sodium hypochlorite - an unstable salt (NaOCl) used as a bleaching agent and disinfectant
sodium salicylate - a crystalline salt used as an analgesic and antipyretic
sodium thiosulfate - a compound used as a fixing agent in photographic developing
sodium - a silvery soft waxy metallic element of the alkali metal group; occurs abundantly in natural compounds (especially in salt water); burns with a yellow flame and reacts violently in water; occurs in sea water and in the mineral halite (rock salt)
soft palate - a muscular flap that closes off the nasopharynx during swallowing or speaking
solubility - the quality of being soluble and easily dissolved in liquid; the quantity of a particular substance that can dissolve in a particular solvent (yielding a saturated solution); the property (of a problem or difficulty) that makes it possible to solve
solution - the successful action of solving a problem; a method for solving a problem; a statement that solves a problem or explains how to solve the problem; the set of values that give a true statement when substituted into an equation; a homogeneous mixture of two or more substances; frequently (but not necessarily) a liquid solution
solvent - capable of meeting financial obligations; a liquid substance capable of dissolving other substances; a statement that solves a problem or explains how to solve the problem
somnambulism - walking by a person who is asleep
somnolence - a very sleepy state
soot - a black colloidal substance consisting wholly or principally of amorphous carbon and used to make pigments and ink; verb coat with soot
sore throat - inflammation of the fauces and pharynx
soybean oil - oil from soya beans
spasm - (pathology) sudden constriction of a hollow organ (as a blood vessel); a painful and involuntary muscular contraction
spasticity - the quality of moving or acting in spasms
special education - education of physically or mentally handicapped children whose needs cannot be met in an ordinary classroom
specific gravity - the density of a substance relative to the density of water
specimen - a bit of tissue or blood or urine that is taken for diagnostic purposes; an example regarded as typical of its class
spectinomycin - an antibiotic used to treat gonorrhea
spectrometry - the use of spectroscopes to analyze spectra
spectrophotometer - a photometer for comparing two light radiations wavelength by wavelength
spectrum analysis - the use of spectroscopes to analyze spectra
speculum - a medical instrument for dilating a bodily passage or cavity in order to examine the interior; a mirror (especially one made of polished metal) for use in an optical instrument
speech disorder - a disorder of oral speech
speech therapy - any therapy intended to correct a disorder of speech
speech - (language) communication by word of mouth; the exchange of spoken words; something spoken; the mental faculty or power of vocal communication; a lengthy rebuke; words making up the dialogue of a play; your characteristic style or manner of expressing yourself orally; the act of delivering a formal spoken communication to an audience
sperm cell - the male reproductive cell; the male gamete
spermatic cord - a structure resembling a cord that suspends the testis within the scrotum and contains the vas deferens and other vessels and nerves
spermatid - an immature gamete produced by a spermatocyte; develops into a spermatozoon
spermatocele - a swelling on the epididymis or the testis; usually contains spermatozoa
spermatocyte - a male gametocyte that develops into four spermatids
spermatogenesis - development of spermatozoa
spermicide - a contraceptive agent that kills spermatozoa
sphincter - a ring of muscle that contracts to close an opening
sphygmomanometer - a pressure gauge for measuring blood pressure
spina bifida - a not uncommon congenital defect in which a vertebra is malformed; unless several vertebrae are affected or there is myelomeningocele there are few symptoms; can be diagnosed by amniocentesis
spinal cord - a major part of the central nervous system which conducts sensory and motor nerve impulses to and from the brain; a long tubelike structure extending from the base of the brain through the vertebral canal to the upper lumbar region
spinal nerve - any of the 31 pairs of nerves emerging from each side of the spinal cord (each attached to the cord by two roots: ventral and dorsal)
spirillum minus - a bacterium causing ratbite fever
spirillum - any flagellated aerobic bacteria having a spirally twisted rodlike form; spirally twisted elongate rodlike bacteria usually living in stagnant water
spirituality - concern with things of the spirit; property or income owned by a church
spirochaetaceae - large coarsely spiral bacteria; free-living in fresh or salt water or commensal in bodies of oysters
spirometry - the use of a spirometer to measure vital capacity
spironolactone - a synthetic corticosteroid (trade name Aldactone) used to treat hypertension
splanchnic nerve - any of several nerves of the sympathetic part of the autonomic nervous system that innervate viscera and blood vessels
spleen - a large dark-red oval organ on the left side of the body between the stomach and the diaphragm; produces cells involved in immune responses; a feeling of resentful anger
splenectomy - surgical removal of the spleen
splenomegaly - an abnormal enlargement of the spleen
spondylarthritis - arthritis that affects one or more of the intervertebral joints in the spine
spondylitis - inflammation of a spinal joint; characterized by pain and stiffness
spondylolisthesis - a forward dislocation of one vertebra over the one beneath it producing pressure on spinal nerves
sponge - primitive multicellular marine animal whose porous body is supported by a fibrous skeletal framework; usually occurs in sessile colonies; a porous mass of interlacing fibers the forms the internal skeleton of various marine animals and usable to absorb water or any porous rubber or cellulose product similarly used; a follower who hangs around a host (without benefit to the host) in hope of gain or advantage; someone able to acquire new knowledge and skills rapidly and easily; verb gather sponges, in the ocean; wipe with a sponge, so as to clean or moisten; soak up with a sponge; erase with a sponge; as of words on a blackboard; ask for and get free; be a parasite
spontaneous abortion - a natural loss of the products of conception
sports medicine - the branch of medicine concerned with the treatment of injuries or illness resulting from athletic activities
spouse - a person's partner in marriage
sprain - a painful injury to a joint caused by a sudden wrenching of its ligaments; verb twist suddenly so as to sprain
sputum - expectorated matter; saliva mixed with discharges from the respiratory passages; in ancient and medieval physiology it was believed to cause sluggishness
squamous cell carcinoma - the most common form of skin cancer
staining - (histology) the use of a dye to color specimens for microscopic study; the act of spotting or staining something
staphylococcus - spherical Gram-positive parasitic bacteria that tend to form irregular colonies; some cause boils or septicemia or infections
starch - a complex carbohydrate found chiefly in seeds, fruits, tubers, roots and stem pith of plants, notably in corn, potatoes, wheat, and rice; an important foodstuff and used otherwise especially in adhesives and as fillers and stiffeners for paper and textiles; verb stiffen with starch
startle reflex - a normal reflex of young infants; a sudden loud noise causes the child to stretch out the arms and flex the legs
starvation - the act of depriving of food or subjecting to famine; a state of extreme hunger resulting from lack of essential nutrients over a prolonged period
statistical distribution - (statistics) an arrangement of values of a variable showing their observed or theoretical frequency of occurrence
status asthmaticus - a prolonged and severe asthma attack that does not respond to standard treatment
status epilepticus - a condition in which there are continuing attacks of epilepsy without intervals of consciousness; can lead to brain damage and death
status - the relative position or standing of things or especially persons in a society; a state at a particular time
stearic acid - a waxy saturated fatty acid; occurs widely as a glyceride in animal and vegetable fats
steatorrhea - the presence of greater than normal amounts of fat in the feces which are frothy and foul smelling and floating; a symptom of disorders of fat metabolism and malabsorption syndrome
stem cell - an undifferentiated cell whose daughter cells may differentiate into other cell types (such as blood cells)
stenosis - abnormal narrowing of a bodily canal or passageway
stent - a slender tube inserted inside a tubular body part (as a blood vessel) to provide support during and after surgical anastomosis
sternum - the flat bone that articulates with the clavicles and the first seven pairs of ribs
steroid hormone - any hormone affecting the development and growth of sex organs
steroid - any of several fat-soluble organic compounds having as a basis 17 carbon atoms in four rings; many have important physiological effects; any hormone affecting the development and growth of sex organs
sterol - any of a group of natural steroid alcohols derived from plants or animals; they are waxy insoluble substances
stillbirth - a natural loss of the products of conception
stoichiometry - (chemistry) the relation between the quantities of substances that take part in a reaction or form a compound (typically a ratio of whole integers)
stomach - an enlarged and muscular saclike organ of the alimentary canal; the principal organ of digestion; an appetite for food; an inclination or liking for things involving conflict or difficulty or unpleasantness; the region of the body of a vertebrate between the thorax and the pelvis; verb bear to eat; put up with something or somebody unpleasant
stomatitis - inflammation of the mucous membrane of the mouth
storage - the act of storing something; the commercial enterprise of storing goods and materials; (computer science) the process of storing information in a computer memory or on a magnetic tape or disk; depositing in a warehouse; an electronic memory device; a depository for goods
strabismus - abnormal alignment of one or both eyes
stratification - the placing of seeds in damp sand or sawdust or peat moss in order to preserve them or promote germination; the act or process or arranging persons into classes or social strata; a layered configuration; forming or depositing in layers; the condition of being arranged in social strata or classes within a group
streptobacillus - any of various rod-shaped Gram-negative bacteria
streptococcus - spherical Gram-positive bacteria occurring in pairs or chains; cause e.g. scarlet fever and tonsillitis
streptokinase - an enzyme produced by some strains of streptococcus that can liquefy blood clots by converting plasminogen to plasmin; used medicinally in some cases of myocardial infarction and pulmonary embolism
streptomyces griseus - source of the antibiotic streptomycin
streptomyces - aerobic bacteria (some of which produce the antibiotic streptomycin)
streptomycetaceae - higher bacteria typically aerobic soil saprophytes
streptomycin - an antibiotic produced by the actinomycete Streptomyces griseus and used to treat tuberculosis
stress fracture - fracture resulting from excessive activity rather than a specific injury
stress - the relative prominence of a syllable or musical note (especially with regard to stress or pitch); (physics) force that produces strain on a physical body; difficulty that causes worry or emotional tension; special emphasis attached to something; (psychology) a state of mental or emotional strain or suspense; verb put stress on; utter with an accent; to stress, single out as important; test the limits of
stressor - any agent that causes stress to an organism
striated muscle - a muscle that is connected at either or both ends to a bone and so move parts of the skeleton; a muscle that is characterized by transverse stripes
stridor - a whistling sound when breathing (usually heard on inspiration); indicates obstruction of the trachea or larynx
stroke - a light touch with the hands; a single complete movement; (sports) the act of swinging or striking at a ball with a club or racket or bat or cue or hand; any one of the repeated movements of the limbs and body used for locomotion in swimming or rowing; a mark made by a writing implement (as in cursive writing); a light touch; the oarsman nearest the stern of the shell who sets the pace for the rest of the crew; a sudden loss of consciousness resulting when the rupture or occlusion of a blood vessel leads to oxygen lack in the brain; a punctuation mark (/) used to separate related items of information; the maximum movement available to a pivoted or reciprocating piece by a cam; verb treat gingerly or carefully; strike a ball with a smooth blow; row at a particular rate; touch lightly and with affection, with brushing motions
stroma - the supporting tissue of an organ (as opposed to parenchyma); the dense colorless framework of a chloroplast; a mass of fungal tissue that has spore-bearing structures embedded in it or on it
strontium - a soft silver-white or yellowish metallic element of the alkali metal group; turns yellow in air; occurs in celestite and strontianite
strychnine - an alkaloid plant toxin extracted chiefly from nux vomica; formerly used as a stimulant
stupor - marginal consciousness; the feeling of distress and disbelief that you have when something bad happens accidentally
stutter - a speech disorder involving hesitations and involuntary repetitions of certain sounds; verb speak haltingly
subacute - less than acute; relating to a disease present in a person with no symptoms of it
subarachnoid space - a space in the meninges beneath the arachnoid membrane and above the pia mater that contains the cerebrospinal fluid
subclavian artery - either of two arteries that supply blood to the neck and arms
sublingual gland - a small salivary gland that produces mucin (the viscous component of saliva); in human beings it is located on either side of the mouth under the tongue
submandibular gland - a salivary gland inside the lower jaw on either side that produces most of the nocturnal saliva; discharges saliva into the mouth under the tongue
submission - the act of submitting; usually surrendering power to another; (law) a contention presented by a lawyer to a judge or jury as part of the case he is arguing; an agreement between parties in a dispute to abide by the decision of an arbiter; a legal document summarizing an agreement between parties in a dispute to abide by the decision of an arbiter; something (manuscripts or architectural plans and models or estimates or works of art of all genres etc.) submitted for the judgment of others (as in a competition); the condition of having submitted to control by someone or something else; the feeling of patient submissive humbleness
submucosa - the connective tissue beneath mucous membrane
substantia nigra - a layer of deeply pigmented grey matter in the midbrain; associated with the striate body; is involved in metabolic disturbances associated with Parkinson's disease and with Huntington's disease
succinylcholine - a muscle relaxant for striated muscle that is used as an adjunct to anesthesia during certain surgical procedures
sucralfate - medicine consisting of a tablet (trade name Carafate) used to treat peptic ulcers; said to bind to the ulcer site and coat it
sucrose - a complex carbohydrate found in many plants and used as a sweetening agent
sudden death - (sports) overtime in which play is stopped as soon as one contestant scores; e.g. football and golf
suffix - an affix that is added at the end of the word; verb attach a suffix to
sugar - a white crystalline carbohydrate used as a sweetener and preservative; informal terms for money; an essential structural component of living cells and source of energy for animals; includes simple sugars with small molecules as well as macromolecular substances; are classified according to the number of monosaccharide groups they contain; verb sweeten with sugar
suicide - the act of killing yourself; a person who kills himself intentionally
sulfacetamide - a topical sulfonamide (trade name Sulamyd) used to treat eye infections
sulfadiazine - a sulfa drug used in treating meningitis and pneumonia and other infections
sulfamethazine - a sulfa drug used like sulfadiazine and also in veterinary medicine
sulfamethoxazole - a sulfonamide (trade name Gantanol) used to treat infections (especially infections of the urinary tract)
sulfanilamide - a white odorless crystalline sulfa drug; the parent compound of most of the sulfa drugs
sulfapyridine - sulfa drug derived from pyridine and sulfanilamide
sulfide - a compound of sulphur and some other element that is more electropositive
sulfisoxazole - a sulfonamide (trade name Gantrisin) used to treat infections of the urinary tract
sulfonamide - antibacterial consisting of any of several synthetic organic compounds capable of inhibiting the growth of bacteria that require PABA
sulfur hexafluoride - a colorless gas that is soluble in alcohol and ether; a powerful greenhouse gas widely used in the electrical utility industry
sulfur - an abundant tasteless odorless multivalent nonmetallic element; best known in yellow crystals; occurs in many sulphide and sulphate minerals and even in native form (especially in volcanic regions); verb treat with sulphur in order to preserve
sulindac - a nonsteroidal anti-inflammatory drug (trade name Clinoril)
sunburn - redness of the skin caused by exposure to the rays of the sun; a browning of the skin resulting from exposure to the rays of the sun; verb get a sunburn by overexposure to the sun
sunscreen - a cream spread on the skin; contains a chemical (as PABA) to filter out ultraviolet light and so protect from sunburn
sunstroke - sudden prostration due to exposure to the sun or excessive heat
superficial - being or affecting or concerned with a surface; not deep or penetrating emotionally or intellectually; of little substance or significance; relating to a surface; involving a surface only
superior colliculus - an essential visual center between the retina and the striate cortex
superior vena cava - receives blood from the head and arms and chest and empties into the right atrium of the heart; formed from the azygos and both brachiocephalic veins
supernumerary - more than is needed, desired, or required; a minor actor in crowd scenes; a person serving no apparent function
superoxide dismutase - an enzyme that catalyzes the conversion of superoxide into hydrogen peroxide and oxygen
superoxide - the univalent anion O2-; a metallic oxide containing the univalent anion O2-
supine - lying face upward; offering no resistance
suppository - a small plug of medication designed for insertion into the rectum or vagina where it melts
suppuration - a fluid product of inflammation; (medicine) the formation of morbific matter in an abscess or a vesicle and the discharge of pus
surface - on the surface; involving a surface only; the outer boundary of an artifact or a material layer constituting or resembling such a boundary; a superficial aspect as opposed to the real nature of something; the extended two-dimensional outer boundary of a three-dimensional object; the outermost level of the land or sea; a device that provides reactive force when in motion relative to the surrounding air; can lift or control a plane in flight; information that has become public; verb come to the surface; appear or become visible; make a showing; put a coat on; cover the surface of; furnish with a surface
surgeon - a physician who specializes in surgery
surgical incision - the cutting of or into body tissues or organs (especially by a surgeon as part of an operation)
survivor - an animal that survives in spite of adversity; one who outlives another; one who lives through affliction
suspension - a temporary debarment (from a privilege or position etc); the act of suspending something (hanging it from above so it moves freely); a mechanical system of springs or shock absorbers connecting the wheels and axles to the chassis of a wheeled vehicle; an interruption in the intensity or amount of something; a mixture in which fine particles are suspended in a fluid where they are supported by buoyancy; temporary cessation or suspension; a time interval during which there is a temporary cessation of something
suture - thread of catgut or silk or wire used by surgeons to stitch tissues together; a seam used in surgery; an immovable joint (especially between the bones of the skull); verb join with a suture
swab - cleaning implement consisting of absorbent material fastened to a handle; for cleaning floors; implement consisting of a small piece of cotton that is used to apply medication or cleanse a wound or obtain a specimen of a secretion; verb wash with a swab or a mop; apply (usually a liquid) to a surface
sweat gland - any of the glands in the skin that secrete perspiration
sweat - condensation of moisture on a cold surface; use of physical or mental energy; hard work; salty fluid secreted by sweat glands; agitation resulting from active worry; verb excrete perspiration through the pores in the skin
sweating - being wet with perspiration; the process of the sweat glands of the skin secreting a salty fluid
symbolism - the practice of investing things with symbolic meaning; a system of symbols and symbolic representations; an artistic movement in the late 19th century that tried to express abstract or mystical ideas through the symbolic use of images
sympathectomy - surgical interruption of a nerve pathway in the sympathetic nervous system
symptom - anything that accompanies X and is regarded as an indication of X's existence; (medicine) any sensation or change in bodily function that is experienced by a patient and is associated with a particular disease
symptomatic - relating to or according to or affecting a symptom or symptoms; characteristic or indicative of e.g. a disease
synapse - the junction between two neurons (axon-to-dendrite) or between a neuron and a muscle
syncope - (phonology) the loss of sounds in the interior of a word (as in `fo'c'sle' for `forecastle'); a spontaneous loss of consciousness caused by insufficient blood to the brain
syndactyly - birth defect in which there is partial or total webbing connecting two or more fingers or toes
syndrome - a complex of concurrent things; a pattern of symptoms indicative of some disease
synovial fluid - viscid lubricating fluid secreted by the membrane lining joints and tendon sheaths etc.
synovial membrane - a thin membrane in synovial (freely moving) joints that lines the joint capsule and secretes synovial fluid
synovitis - inflammation of the synovial membrane that lines a synovial joint; results in pain and swelling
syntax - the grammatical arrangement of words in sentences; studies of the rules for forming admissible sentences; a systematic orderly arrangement
synthesis - the combination of ideas into a complex whole; the process of producing a chemical compound (usually by the union of simpler chemical compounds); reasoning from the general to the particular (or from cause to effect)
syphilis - a common venereal disease caused by the treponema pallidum spirochete; symptoms change through progressive stages; can be congenital (transmitted through the placenta)
syringe - a medical instrument used to inject or withdraw fluids; verb spray or irrigate (a body part) with a syringe
systolic pressure - the blood pressure (as measured by a sphygmomanometer) during the contraction of the left ventricle of the heart
t lymphocyte - a small lymphocyte developed in the thymus; it orchestrates the immune system's response to infected or malignant cells
tabes dorsalis - syphilis of the spinal cord characterized by degeneration of sensory neurons and stabbing pains in the trunk and legs and unsteady gait and incontinence and impotence
tablet - a small flat compressed cake of some substance; a slab of stone or wood suitable for bearing an inscription; a dose of medicine in the form of a small pellet; a number of sheets of paper fastened together along one edge
tachycardia - abnormally rapid heartbeat (over 100 beats per minute)
tactile agnosia - a loss of the ability to recognize objects by handling them
tadalafil - virility drug (trade name Cialis) used to treat erectile dysfunction in men
taenia - tapeworms parasitic in humans which uses the pig as its intermediate host; a narrow headband or strip of ribbon worn as a headband
tail - the posterior part of the body of a vertebrate especially when elongated and extending beyond the trunk or main part of the body; the rear part of an aircraft; (usually plural) the reverse side of a coin that does not bear the representation of a person's head; a spy employed to follow someone and report their movements; any projection that resembles the tail of an animal; the rear part of a ship; the fleshy part of the human body that you sit on; the time of the last part of something; verb remove the stalk of fruits or berries; remove or shorten the tail of an animal; go after with the intent to catch
talc - a fine grained mineral having a soft soapy feel and consisting of hydrated magnesium silicate; used in a variety of products including talcum powder; verb apply talcum powder to (one's body)
talipes - congenital deformity of the foot usually marked by a curled shape or twisted position of the ankle and heel and toes
talus - a sloping mass of loose rocks at the base of a cliff; the bone in the ankle that articulates with the leg bones to form the ankle joint
tamoxifen - an antagonist for estrogen that is used in the treatment of breast cancer
tannic acid - any of various complex phenolic substances of plant origin; used in tanning and in medicine
tantalum - a hard grey lustrous metallic element that is highly resistant to corrosion; occurs in niobite and fergusonite and tantalite
tardive dyskinesia - involuntary rolling of the tongue and twitching of the face or trunk or limbs; often occurs in patients with Parkinsonism who are treated with phenothiazine
taste bud - an oval sensory end organ on the surface of the tongue
taste - a kind of sensing; distinguishing substances by means of the taste buds; the faculty of distinguishing sweet, sour, bitter, and salty properties in the mouth; the sensation that results when taste buds in the tongue and throat convey information about the chemical composition of a soluble stimulus; delicate discrimination (especially of aesthetic values); a brief experience of something; a small amount eaten or drunk; a strong liking; verb experience briefly; perceive by the sense of taste; distinguish flavors; have flavor; taste of something; take a sample of; have a distinctive or characteristic taste
taurine - of or relating to or resembling a bull; a colorless crystalline substance obtained from the bile of mammals
tax - charge against a citizen's person or property or activity for the support of government; verb make a charge against or accuse; use to the limit; levy a tax on; set or determine the amount of (a payment such as a fine)
teacher - a personified abstraction that teaches; a person whose occupation is teaching
teat - the small projection of a mammary gland
technetium - a crystalline metallic element not found in nature; occurs as one of the fission products of uranium
technician - someone whose occupation involves training in a specific technical process; someone known for high skill in some intellectual or artistic technique
telemetry - automatic transmission and measurement of data from remote sources by wire or radio or other means
telencephalon - the anterior division of the forebrain; the cerebrum and related parts of the hypothalamus
tellurium - a brittle silver-white metalloid element that is related to selenium and sulfur; it is used in alloys and as a semiconductor; occurs mainly as tellurides in ores of copper and nickel and silver and gold
telomerase - an enzyme in eukaryotic cells that can add telomeres to the ends of chromosomes after they divide
telomere - either (free) end of a eukaryotic chromosome
telophase - the final stage of mitosis; the final stage of meiosis when the chromosomes move toward opposite ends of the nuclear spindle
temazepam - a frequently prescribed benzodiazepine (trade name Restoril); takes effect slowly and lasts long enough to help those people who wake up frequently during the night
temperament - an adjustment of the intervals (as in tuning a keyboard instrument) so that the scale can be used to play in different keys; excessive emotionalism or irritability and excitability (especially when displayed openly); your usual mood
temperature - the degree of hotness or coldness of a body or environment (corresponding to its molecular activity); the somatic sensation of cold or heat
temporal arteritis - inflammation of the temporal arteries; characterized by headaches and difficulty chewing and (sometimes) visual impairment
temporal bone - a thick bone forming the side of the human cranium and encasing the inner ear
temporal lobe - that part of the cerebral cortex in either hemisphere of the brain lying inside the temples of the head
temporomandibular joint - the joint between the head of the lower jawbone and the temporal bone
tendinitis - inflammation of a tendon
tendon - a cord or band of inelastic tissue connecting a muscle with its bony attachment
tennis elbow - painful inflammation of the tendon at the outer border of the elbow resulting from overuse of lower arm muscles (as in twisting of the hand)
tenosynovitis - inflammation of a tendon and its enveloping sheath
tensile strength - the strength of material expressed as the greatest longitudinal stress it can bear without tearing apart
teratogenesis - the development of defects in an embryo
teratoma - a tumor consisting of a mixture of tissues not normally found at that site
terazosin - antihypertensive drug (trade name Hytrin) used to treat high blood pressure
terpene - an unsaturated hydrocarbon obtained from plants
testis - one of the two male reproductive glands that produce spermatozoa and secrete androgens
testosterone - a potent androgenic hormone produced chiefly by the testes; responsible for the development of male secondary sex characteristics
tetanus - a sustained muscular contraction resulting from a rapid series of nerve impulses; an acute and serious infection of the central nervous system caused by bacterial infection of open wounds; spasms of the jaw and laryngeal muscles may occur during the late stages
tetany - clinical neurological syndrome characterized by muscular twitching and cramps and (when severe) seizures; associated with calcium deficiency (hypoparathyroidism) or vitamin D deficiency or alkalosis
tetracaine - a crystalline compound used in the form of a hydrochloride as a local anesthetic
tetrachloroethylene - anthelmintic agent used against hookworm and other nematodes
tetracycline - an antibiotic (trade name Achromycin) derived from microorganisms of the genus Streptomyces and used broadly to treat infections
tetrahymena - relative of the paramecium; often used in genetics research
tetralogy of fallot - a congenital heart defect producing cyanosis; characterized by four symptoms: pulmonary stenosis and ventricular septal defect and malposition of the aorta over both ventricles and hypertrophy of the right ventricle
tetrodotoxin - a powerful neurotoxin found in the ovaries of pufferfish
thalamus - large egg-shaped structures of grey matter that form the dorsal subdivision of the diencephalon
thalassemia - an inherited form of anemia caused by faulty synthesis of hemoglobin
thalidomide - a sedative and hypnotic drug; withdrawn from sale after discovered to cause severe birth defects because it inhibits angiogenesis
thallium - a soft grey malleable metallic element that resembles tin but discolors on exposure to air; it is highly toxic and is used in rodent and insect poisons; occurs in zinc blende and some iron ores
thaw - a relaxation or slackening of tensions or reserve; becoming less hostile; warm weather following a freeze; snow and ice melt; the process whereby heat changes something from a solid to a liquid; verb become or cause to become soft or liquid
theophylline - a colorless crystalline alkaloid derived from tea leaves or made synthetically; used in medicine as a bronchial dilator
therapeutic abortion - a legally induced abortion for medical reasons (as when the mother's life is threatened)
therapeutic - relating to or involved in therapy; tending to cure or restore to health; a medicine or therapy that cures disease or relieve pain
therapy - (medicine) the act of caring for someone (as by medication or remedial training etc.)
thermodynamics - the branch of physics concerned with the conversion of different forms of energy
thermography - diagnostic technique using a thermograph to record the heat produced by different parts of the body; used to study blood flow and to detect tumors
thermogravimetry - the measurement of changes in weight as a function of changes in temperature used as a technique of chemically analyzing substances
thermoreceptor - a sensory receptor that responds to heat and cold
thiabendazole - an antifungal agent and anthelmintic
thiamine pyrophosphate - a coenzyme important in respiration in the Krebs cycle
thiamine - a B vitamin that prevents beriberi; maintains appetite and growth
thiazide - any of a group of drugs commonly used as diuretics in the treatment of hypertension; they block the reabsorption of sodium in the kidneys
thick - abounding; having a lot of; (of darkness) very intense; not thin; of a specific thickness or of relatively great extent from one surface to the opposite usually in the smallest of the three solid dimensions; relatively dense in consistency; used informally; (used informally) associated on close terms; having component parts closely crowded together; heavy and compact in form or stature; spoken as if with a thick tongue; hard to pass through because of dense growth; in quick succession; with a thick consistency; the location of something surrounded by other things
thigh - the part of the leg between the hip and the knee; the upper joint of the leg of a fowl
thimerosal - a light-colored crystalline powder (trade name Merthiolate) used as a surgical antiseptic
thinking - endowed with the capacity to reason; the process of using your mind to consider something carefully
thiocyanate - a salt of thiocyanic acid; formed when alkaline cyanides are fused with sulfur
thioguanine - an antineoplastic drug used to treat acute leukemias
thiopental - barbiturate that is a hygroscopic powder (trade name Pentothal) that is a strong barbiturate that acts rapidly; induces a relaxed state when injected as a general anesthetic
thioridazine - a tranquilizer (trade name Mellaril) used to treat schizophrenia and other psychotic disorders
thiotepa - an antineoplastic drug used to treat certain malignancies
thiothixene - a tranquilizer (trade name Navane) used to treat schizophrenia
thiouracil - depresses the function of the thyroid gland
thirst - a physiological need to drink; strong desire for something (not food or drink); verb feel the need to drink; have a craving, appetite, or great desire for
thoracentesis - removal of fluid from the chest by centesis for diagnostic or therapeutic purposes
thoracic aorta - a branch of the descending aorta; divides into the iliac arteries
thoracic cavity - the cavity in the vertebrate body enclosed by the ribs between the diaphragm and the neck and containing the lungs and heart
thoracic duct - the major duct of the lymphatic system
thoracotomy - surgical incision into the chest walls opening up the pleural cavity
thorax - part of an insect's body that bears the wings and legs; the part of the human torso between the neck and the diaphragm or the corresponding part in other vertebrates; the middle region of the body of an arthropod between the head and the abdomen
threatened abortion - the appearance of symptoms that signal the impending loss of the products of conception
threonine - a colorless crystalline amino acid found in protein; occurs in the hydrolysates of certain proteins; an essential component of human nutrition
throat - a passage resembling a throat in shape or function; an opening in the vamp of a shoe at the instep; the passage to the stomach and lungs; in the front part of the neck below the chin and above the collarbone
thrombasthenia - a rare autosomal recessive disease in which the platelets do not produce clots in the normal way and hemorrhage results
thrombectomy - surgical removal of a blood clot (thrombus) from a blood vessel
thrombin - an enzyme that acts on fibrinogen in blood causing it to clot
thrombocytopenia - a blood disease characterized by an abnormally small number of platelets in the blood
thrombocytopenic purpura - purpura associated with a reduction in circulating blood platelets which can result from a variety of factors
thrombocytosis - increase in the number of platelets in the blood which tends to cause clots to form; associated with many neoplasms and chronic infections and other diseases
thromboembolism - occlusion of a blood vessel by an embolus that has broken away from a thrombus
thrombophlebitis - phlebitis in conjunction with the formation of a blood clot (thrombus)
thromboplastin - an enzyme liberated from blood platelets that converts prothrombin into thrombin as blood starts to clot
thrombosis - the formation or presence of a thrombus (a clot of coagulated blood attached at the site of its formation) in a blood vessel
thymidine - a nucleoside component of DNA; composed of thymine and deoxyribose
thymine - a base found in DNA (but not in RNA) and derived from pyrimidine; pairs with adenine
thymol - a colorless crystalline solid used in perfume or preserving biological specimens or in embalming or medically as a fungicide or antiseptic
thymosin - hormone secreted by the thymus; stimulates immunological activity of lymphoid tissue
thymus - large genus of Old World mints: thyme; a ductless glandular organ at the base of the neck that produces lymphocytes and aids in producing immunity; atrophies with age
thyroglobulin - an iodine containing protein that is obtained from the thyroid gland and exhibits the general properties of the globulins
thyroid gland - located near the base of the neck
thyroid hormone - any of several closely related compounds that are produced by the thyroid gland and are active metabolically
thyroidectomy - surgical removal of the thyroid gland
thyroiditis - inflammation of the thyroid gland
thyrotoxicosis - an overactive thyroid gland; pathologically excessive production of thyroid hormones or the condition resulting from excessive production of thyroid hormones
thyrotropin - anterior pituitary hormone that stimulates the function of the thyroid gland
tibia - the inner and thicker of the two bones of the human leg between the knee and ankle
timolol - a beta blocker (trade name Blocadren) administered after heart attacks
tincture - (pharmacology) a medicine consisting of an extract in an alcohol solution; a substances that colors metals; a quality of a given color that differs slightly from a primary color; an indication that something has been present; verb stain or tint with a color; fill, as with a certain quality
tinea capitis - fungal infection of the scalp characterized by bald patches
tinea pedis - fungal infection of the feet
tinea - type genus of the Tineidae: clothes moths; infections of the skin or nails caused by fungi and appearing as itching circular patches
tinnitus - a ringing or booming sensation in one or both ears; a symptom of an ear infection or Meniere's disease
tissue - part of an organism consisting of an aggregate of cells having a similar structure and function; a soft thin (usually translucent) paper; verb create a piece of cloth by interlacing strands of fabric, such as wool or cotton
titanium - a light strong grey lustrous corrosion-resistant metallic element used in strong lightweight alloys (as for airplane parts); the main sources are rutile and ilmenite
tobacco - leaves of the tobacco plant dried and prepared for smoking or ingestion; aromatic annual or perennial herbs and shrubs
tobramycin - an antibiotic (trade name Nebcin) that is especially effective against Gram-negative bacteria
toe - having a toe or toes of a specified kind; often used in combination; the part of footwear that provides a covering for the toes; (golf) the part of a clubhead farthest from the shaft; one of the digits of the foot; forepart of a hoof; verb touch with the toe; drive (a golf ball) with the toe of the club; hit (a golf ball) with the toe of the club; drive obliquely; walk so that the toes assume an indicated position or direction
togaviridae - a family of arboviruses carried by arthropods
tolazamide - a drug (trade name Tolinase) used in treating stable adult-onset diabetes mellitus
tolbutamide - sulfonylurea; an oral antidiabetic drug (trade name Orinase) used in the treatment of adult-onset diabetes mellitus
tolerance - the act of tolerating something; the power or capacity of an organism to tolerate unfavorable environmental conditions; willingness to recognize and respect the beliefs or practices of others; a disposition to allow freedom of choice and behavior; a permissible difference; allowing some freedom to move within limits
toluene - a colorless flammable liquid obtained from petroleum or coal tar; used as a solvent for gums and lacquers and in high-octane fuels
tomography - (medicine) obtaining pictures of the interior of the body
tongue - the flap of material under the laces of a shoe or boot; a mobile mass of muscular tissue covered with mucous membrane and located in the oral cavity; a manner of speaking; the tongue of certain animals used as meat; any long thin projection that is transient; metal striker that hangs inside a bell and makes a sound by hitting the side; a human written or spoken language used by a community; opposed to e.g. a computer language; a narrow strip of land that juts out into the sea; verb lick or explore with the tongue; articulate by tonguing, as when playing wind instruments
tonometer - measuring instrument for measuring tension or pressure (especially for measuring intraocular pressure in testing for glaucoma)
tonsil - either of two masses of lymphatic tissue one on each side of the oral pharynx
tonsillectomy - surgical removal of the palatine tonsils; commonly performed along with adenoidectomy
tonsillitis - inflammation of the tonsils (especially the palatine tonsils)
tooth enamel - hard white substance covering the crown of a tooth
tooth root - the part of a tooth that is embedded in the jaw and serves as support
tooth - a means of enforcement; toothlike structure in invertebrates found in the mouth or alimentary canal or on a shell; something resembling the tooth of an animal; one of a number of uniform projections on a gear; hard bonelike structures in the jaws of vertebrates; used for biting and chewing or for attack and defense
toothache - an ache localized in or around a tooth
toothpaste - a dentifrice in the form of a paste
topical - of interest at the present time; pertaining to the surface of a body part; of or relating to or arranged by topics
torticollis - an unnatural condition in which the head leans to one side because the neck muscles on that side are contracted
tourette's syndrome - neurological disorder characterized by facial grimaces and tics and movements of the upper body and grunts and shouts and coprolalia
tourniquet - bandage that stops the flow of blood from an artery by applying pressure
toxic shock syndrome - syndrome resulting from a serious acute (sometimes fatal) infection associated with the presence of staphylococcus; characterized by fever and diarrhea and nausea and diffuse erythema and shock; occurs especially in menstruating women using highly absorbent tampons
toxic - of or relating to or caused by a toxin or poison
toxicology - the branch of pharmacology that deals with the nature and effects and treatments of poisons
toxin - a poisonous substance produced during the metabolism and growth of certain microorganisms and some higher plant and animal species
toxoid - a bacterial toxin that has been weakened until it is no longer toxic but is strong enough to induce the formation of antibodies and immunity to the specific disease caused by the toxin
toxoplasmosis - infection caused by parasites transmitted to humans from infected cats; if contracted by a pregnant woman it can result in serious damage to the fetus
trace element - an element that occurs at very small quantities in the body but is nonetheless important for many biological processes
tracer - ammunition whose flight can be observed by a trail of smoke; (radiology) any radioactive isotope introduced into the body to study metabolism or other biological processes; an instrument used to make tracings; an investigator who is employed to find missing persons or missing goods
trachea - membranous tube with cartilaginous rings that conveys inhaled air from the larynx to the bronchi; one of the tubules forming the respiratory system of most insects and many arachnids
tracheitis - inflammation of the trachea
tracheostomy - a surgical operation that creates an opening into the trachea with a tube inserted to provide a passage for air; performed when the pharynx is obstructed by edema or cancer or other causes
trachoma - a chronic contagious viral disease marked by inflammation of the conjunctiva and cornea of the eye and the formation of scar tissue
traction - (orthopedics) the act of pulling on a bone or limb (as in a fracture) to relieve pressure or align parts in a special way during healing; the friction between a body and the surface on which it moves (as between an automobile tire and the road)
transaminase - a class of transferases that catalyze transamination (that transfer an amino group from an amino acid to another compound)
transdermal - through the unbroken skin; refers to medications applied directly to the skin (creams or ointments) or in time-release forms (skin patches)
transfer rna - RNA molecules present in the cell (in at least 20 varieties, each variety capable of combining with a specific amino acid) that attach the correct amino acid to the protein chain that is being synthesized at the ribosome of the cell (according to directions coded in the mRNA)
transferase - any of various enzymes that move a chemical group from one compound to another compound
transferrin - a globulin in blood plasma that carries iron
transient ischemic attack - brief episode in which the brain gets insufficient blood supply; symptoms depend on the site of the blockage
transmission - the act of sending a message; causing a message to be transmitted; the gears that transmit power from an automobile engine via the driveshaft to the live axle; communication by means of transmitted signals; an incident in which an infectious disease is transmitted; the fraction of radiant energy that passes through a substance
transplantation - the act of removing something from one location and introducing it in another location; an operation moving an organ from one organism (the donor) to another (the recipient)
transverse colon - the part of the large intestine that extends across the abdominal cavity and joins the ascending to the descending colon
transvestism - the practice of adopting the clothes or the manner or the sexual role of the opposite sex
trazodone - oral antidepressant (trade name Desyrel) that is a nontricyclic drug used as a sedative
trematoda - parasitic flatworms (including flukes)
tremor - an involuntary vibration (as if from illness or fear); a small earthquake; shaking or trembling (usually resulting from weakness or stress or disease); verb shake with seismic vibrations
trephine - a surgical instrument used to remove sections of bone from the skull; verb operate on with a trephine
treponema - spirochete that causes disease in humans (e.g. syphilis and yaws)
triamcinolone - a synthetic corticosteroid (trade names Aristocort or Aristopak or Kenalog) used as an anti-inflammatory agent
triazine - any of three isomeric compounds having three carbon and three nitrogen atoms in a six-membered ring
triazolam - a form of benzodiazepine (trade name Halcion) frequently prescribed as a sleeping pill; usually given to people who have trouble falling asleep
tributyrin - a bitter oily triglyceride of butyric acid; a form of butyrin
trichinella spiralis - parasitic nematode occurring in the intestines of pigs and rats and human beings and producing larvae that form cysts in skeletal muscles
trichlormethiazide - diuretic drug (trade name Naqua) used to treat hypertension
trichloroethylene - a heavy colorless highly toxic liquid used as a solvent to clean electronic components and for dry cleaning and as a fumigant; causes cancer and liver and lung damage
trichotillomania - an irresistible urge to pull out your own hair
tricuspid valve - valve with three cusps; situated between the right atrium and the right ventricle; allows blood to pass from atrium to ventricle and closes to prevent backflow when the ventricle contracts
tricyclic antidepressant - an antidepressant drug that acts by blocking the reuptake of norepinephrine and serotonin and thus making more of those substances available to act on receptors in the brain
trigeminal nerve - the main sensory nerve of the face and motor nerve for the muscles of mastication
trigeminal neuralgia - intense paroxysmal neuralgia along the trigeminal nerve
triglyceride - glyceride occurring naturally in animal and vegetable tissues; it consists of three individual fatty acids bound together in a single large molecule; an important energy source forming much of the fat stored by the body
triose - any monosaccharide sugar containing three atoms of carbon per molecule
trismus - prolonged spasm of the jaw muscles
trisomy - chrosomal abnormality in which there is one more than the normal number of chromosomes in a cell
tritium - a radioactive isotope of hydrogen; atoms of tritium have three times the mass of ordinary hydrogen atoms
trophoblast - the membrane that forms the wall of the blastocyst in early development; aids implantation in the uterine wall
tropism - an involuntary orienting response; positive or negative reaction to a stimulus source
trunk - luggage consisting of a large strong case used when traveling or for storage; the main stem of a tree; usually covered with bark; the bole is usually the part that is commercially useful for lumber; a long flexible snout as of an elephant; compartment in an automobile that carries luggage or shopping or tools; the body excluding the head and neck and limbs
trypsin - an enzyme of pancreatic origin; catalyzes the hydrolysis of proteins to smaller polypeptide units
trypsinogen - inactive precursor of trypsin; a substance secreted by the pancreas and converted to active trypsin by enterokinase in the small intestine
tryptophan - an amino acid that occurs in proteins; is essential for growth and normal metabolism; a precursor of niacin
tubal ligation - a sterilization procedure with women; both Fallopian tubes are tied in two places and the tubes removed in between the ligations
tuberculin test - a skin test to determine past or present infection with the tuberculosis bacterium; based on hypersensitivity of the skin to tuberculin
tuberculin - a sterile liquid containing a purified protein derivative of the tuberculosis bacterium; used in the diagnosis of tuberculosis
tuberculosis - infection transmitted by inhalation or ingestion of tubercle bacilli and manifested in fever and small lesions (usually in the lungs but in various other parts of the body in acute stages)
tubocurarine - a toxic alkaloid found in certain tropical South American trees that is a powerful relaxant for striated muscles
tularemia - a highly infectious disease of rodents (especially rabbits and squirrels) and sometimes transmitted to humans by ticks or flies or by handling infected animals
tungsten - a heavy grey-white metallic element; the pure form is used mainly in electrical applications; it is found in several ores including wolframite and scheelite
turner's syndrome - a chromosomal disorder in females who have only one X chromosome; marked by dwarfism and heart abnormalities and underdeveloped sex organs
turpentine - volatile liquid distilled from turpentine oleoresin; used as paint thinner and solvent and medicinally; obtained from conifers (especially pines)
twin - being two identical; very similar; a waterfall in the Snake River in southern Idaho; either of two offspring born at the same time from the same pregnancy; a duplicate copy; (astrology) a person who is born while the sun is in Gemini; verb give birth to twins; grow as twins; duplicate or match; bring two objects, ideas, or people together
tympanoplasty - surgical correction or repair of defects or injuries in the eardrum or the bones of the middle ear
typhoid - serious infection marked by intestinal inflammation and ulceration; caused by Salmonella typhosa ingested with food or water
tyramine - amino acid derived from tyrosine; has a sympathomimetic action; found in chocolate and cola drinks and ripe cheese and beer
tyrosine - an amino acid found in most proteins; a precursor of several hormones
tyrosinemia - autosomal recessive defect in tyrosine metabolism resulting in liver and kidney disturbances and mental retardation
ubiquinone - any of several quinones found in living cells and that function as coenzymes that transfer electrons from one molecule to another in cell respiration
ulcer - a circumscribed inflammatory and often suppurating lesion on the skin or an internal mucous surface resulting in necrosis of tissue
ulcerative colitis - a serious chronic inflammatory disease of the large intestine and rectum characterized by recurrent episodes of abdominal pain and fever and chills and profuse diarrhea
ulna - the inner and longer of the two bones of the human forearm
ultracentrifugation - centrifugation at very high speeds
ultrasonography - using the reflections of high-frequency sound waves to construct an image of a body organ (a sonogram); commonly used to observe fetal growth or study bodily organs
umbilical cord - membranous duct connecting the fetus with the placenta
umbilical hernia - protrusion of the intestine and omentum through a hernia in the abdominal wall near the navel; usually self correcting after birth
umbilical vein - a vein in the umbilical cord; returns nutrient blood from the placenta to the fetus
uncertainty - being unsettled or in doubt or dependent on chance; the state of being unsure of something
unconsciousness - a state lacking normal awareness of the self or environment
undetermined - not yet having been ascertained or determined; not precisely determined or established; not fixed or known in advance; not brought to a conclusion; subject to further thought
undifferentiated - not differentiated
unequivocal - admitting of no doubt or misunderstanding; having only one meaning or interpretation and leading to only one conclusion; clearly defined or formulated
unexpected - not expected or anticipated; happening or coming quickly and without warning; not planned; made necessary by an unexpected situation or emergency
unilateral - involving only one part or side; tracing descent from either the paternal or the maternal line only
unknown - not known; not known to exist; being or having an unknown or unnamed source; not known before; not famous or acclaimed; a variable whose values are solutions of an equation; an unknown and unexplored region; anyone who does not belong in the environment in which they are found
uracil - a base containing nitrogen that is found in RNA (but not in DNA) and derived from pyrimidine; pairs with adenine
uranium - a heavy toxic silvery-white radioactive metallic element; occurs in many isotopes; used for nuclear fuels and nuclear weapons
urea - the chief solid component of mammalian urine; synthesized from ammonia and carbon dioxide and used as fertilizer and in animal feed and in plastics
uremia - accumulation in the blood of nitrogenous waste products (urea) that are usually excreted in the urine
ureter - either of a pair of thick-walled tubes that carry urine from the kidney to the urinary bladder
ureteritis - inflammation of the ureter
ureterocele - prolapse of the end of the ureter into the bladder; may obstruct urine flow
urethra - duct through which urine is discharged in most mammals and which serves as the male genital duct
urethral sphincter - a striated sphincter muscle that constricts the urethra
urethritis - inflammation of the urethra; results in painful urination
uric acid - a white tasteless odorless crystalline product of protein metabolism; found in the blood and urine
urinal - a plumbing fixture (usually attached to the wall) used by men to urinate
urinalysis - (medicine) the chemical analysis of urine (for medical diagnosis)
urinary bladder - a membranous sac for temporary retention of urine
urinary incontinence - inability to control the flow of urine and involuntary urination
urinary retention - holding urine in the urinary bladder
urinary system - the system that includes all organs involved in reproduction and in the formation and voidance of urine
urinary tract infection - any infection of any of the organs of the urinary tract
urinary tract - the organs and tubes involved in the production and excretion of urine
urinary - of or relating to the function or production or secretion of urine; of or relating to the urinary system of the body
urination - the discharge of urine
urine - liquid excretory product
urochordata - tunicates
urologist - a specialist in urology
urology - the branch of medicine that deals with the diagnosis and treatment of disorders of the urinary tract or urogenital system
urticaria - an itchy skin eruption characterized by weals with pale interiors and well-defined red margins; usually the result of an allergic response to insect bites or food or drugs
ustilago - type genus of the Ustilaginaceae; genus comprising the loose smuts
uterine cavity - the space inside the uterus between the cervical canal and the Fallopian tubes
uterus - a hollow muscular organ in the pelvic cavity of females; contains the developing fetus
uvea - the part of the eye that contains the iris and ciliary body and choroid
uveitis - inflammation of the uvea of the eye
uvula - a small pendant fleshy lobe at the back of the soft palate
vaccination - the scar left following inoculation with a vaccine; taking a vaccine as a precaution against contracting a disease
vaccine - immunogen consisting of a suspension of weakened or dead pathogenic cells injected in order to stimulate the production of antibodies
vacuole - a tiny cavity filled with fluid in the cytoplasm of a cell
vagina - the lower part of the female reproductive tract; a moist canal in female mammals extending from the labia minora to the uterus
vaginal discharge - discharge of secretions from the cervical glands of the vagina; normally clear or white
vaginitis - inflammation of the vagina (usually associated with candidiasis)
vagus nerve - a mixed nerve that supplies the pharynx and larynx and lungs and heart and esophagus and stomach and most of the abdominal viscera
valine - an essential amino acid found in proteins; important for growth in children and nitrogen balance in adults
valproic acid - anticonvulsant (trade name Depokene) used to prevent some kinds of seizures
vanadium - a soft silvery white toxic metallic element used in steel alloys; it occurs in several complex minerals including carnotite and vanadinite
vancomycin - an antibiotic (trade name Vancocin) effective against some bacterial infections
vapor - a visible suspension in the air of particles of some substance; the process of becoming a vapor
varicocele - dilatation of the veins associated with the spermatic cord in the testes
varicose vein - a vein that is permanently dilated; most common in the legs
vas deferens - a duct that carries spermatozoa from the epididymis to the ejaculatory duct
vascular - of or relating to or having vessels that conduct and circulate fluids
vasculitis - inflammation of a blood vessel
vasectomy - surgical procedure that removes all or part of the vas deferens (usually as a means of sterilization); is sometimes reversible
vasoconstriction - decrease in the diameter of blood vessels
vasodilation - dilation of blood vessels (especially the arteries)
vein - one of the horny ribs that stiffen and support the wing of an insect; a blood vessel that carries blood from the capillaries toward the heart; a distinctive style or manner; a layer of ore between layers of rock; any of the vascular bundles or ribs that form the branching framework of conducting and supporting tissues in a leaf or other plant organ; verb make a veinlike pattern
venipuncture - (medicine) puncture of a vein through the skin in order to withdraw blood for analysis or to start an intravenous drip or to inject medication or a radiopaque dye
venom - toxin secreted by animals; secreted by certain snakes and poisonous insects (e.g., spiders and scorpions); feeling a need to see others suffer
venous thrombosis - thrombosis of a vein without prior inflammation of the vein; associated with sluggish blood flow (as in prolonged bedrest or pregnancy or surgery) or with rapid coagulation of the blood
venous - of or contained in or performing the function of the veins
ventilator - a device (such as a fan) that introduces fresh air or expels foul air; a device that facilitates breathing in cases of respiratory failure
ventral - toward or on or near the belly (front of a primate or lower surface of a lower animal); nearest to or facing toward the axis of an organ or organism
ventricle - a chamber of the heart that receives blood from an atrium and pumps it to the arteries; one of four connected cavities in the brain; is continuous with the central canal of the spinal cord and contains cerebrospinal fluid
ventricular fibrillation - fibrillation of heart muscles resulting in interference with rhythmic contractions of the ventricles and possibly leading to cardiac arrest
verapamil - a drug (trade names Calan and Isoptin) used as an oral or parenteral calcium blocker in cases of hypertension or congestive heart failure or angina or migraine
vernier caliper - a caliper with a vernier scale for very fine measurements
vertebra - one of the bony segments of the spinal column
vertebral column - the series of vertebrae forming the axis of the skeleton and protecting the spinal cord
vertebrate - having a backbone or spinal column; animals having a bony or cartilaginous skeleton with a segmented spinal column and a large brain enclosed in a skull or cranium
vertigo - a reeling sensation; a feeling that you are about to fall
vesicle - a small anatomically normal sac or bladderlike structure (especially one containing fluid)
vesiculovirus - an animal virus that causes vesicular stomatitis
veterinarian - a doctor who practices veterinary medicine
veterinary medicine - the branch of medicine that deals with the diagnosis and treatment of diseases and injuries of animals (especially domestic animals)
vibrio - curved rodlike motile bacterium
vinblastine - periwinkle plant derivative used as an antineoplastic drug (trade name Velban) that disrupts cell division
vincristine - periwinkle plant derivative used as an antineoplastic drug (trade name Oncovin); used to treat cancer of the lymphatic system
violence - an act of aggression (as one against a person who resists); a turbulent state resulting in injuries and destruction etc.; the property of being wild or turbulent
viomycin - a basic polypeptide antibiotic (trade name Viocin) administered intramuscularly (along with other drugs) in the treatment of tuberculosis
viral hepatitis - hepatitis caused by a virus
viral - relating to or caused by a virus
viremia - the presence of a virus in the blood stream
virilism - the development of male secondary sexual characteristics in a female (or prematurely in a young boy)
virion - (virology) a complete viral particle; nucleic acid and capsid (and a lipid envelope in some viruses)
viroid - the smallest of viruses; a plant virus with its RNA arranged in a circular chromosome without a protein coat
virulence - extreme hostility; extreme harmfulness (as the capacity of a microorganism to cause disease)
virulent - infectious; having the ability to cause disease; harsh or corrosive in tone; extremely poisonous or injurious; producing venom
virus - (virology) ultramicroscopic infectious agent that replicates itself only within cells of living hosts; many are pathogenic; a piece of nucleic acid (DNA or RNA) wrapped in a thin coat of protein; a software program capable of reproducing itself and usually capable of causing great harm to files or other programs on the same computer; a harmful or corrupting agency
viscera - internal organs collectively (especially those in the abdominal cavity)
visceral pleura - pleura that covers the lungs
visceral - relating to or affecting the viscera; obtained through intuition rather than from reasoning or observation
vision - the perceptual experience of seeing; a vivid mental image; a religious or mystical experience of a supernatural appearance; the formation of a mental image of something that is not perceived as real and is not present to the senses; the ability to see; the visual faculty
visual acuity - sharpness of vision; the visual ability to resolve fine detail (usually measured by a Snellen chart)
visual agnosia - inability to recognize or interpret objects in the visual field
visual cortex - the cortical area that receives information from the lateral geniculate body of the thalamus
visual field - all of the points of the physical environment that can be perceived by a stable eye at a given moment
visual impairment - impairment of the sense of sight
visual perception - perception by means of the eyes
vital sign - sign of life; usually an indicator of a person's general physical condition
vital statistics - data relating to births and deaths and health and diseases and marriages
vitamin a - any of several fat-soluble vitamins essential for normal vision; prevents night blindness or inflammation or dryness of the eyes
vitamin b complex - originally thought to be a single vitamin but now separated into several B vitamins
vitamin b - originally thought to be a single vitamin but now separated into several B vitamins
vitamin d - a fat-soluble vitamin that prevents rickets
vitamin e - a fat-soluble vitamin that is essential for normal reproduction; an important antioxidant that neutralizes free radicals in the body
vitamin k - a fat-soluble vitamin that helps in the clotting of blood
vitamin - any of a group of organic substances essential in small quantities to normal metabolism
vitiligo - an acquired skin disease characterized by patches of unpigmented skin (often surrounded by a heavily pigmented border)
vitreous body - the clear colorless transparent jelly that fills the posterior chamber of the eyeball
vitreous humor - the clear colorless transparent jelly that fills the posterior chamber of the eyeball
vocabulary - a language user's knowledge of words; the system of techniques or symbols serving as a means of expression (as in arts or crafts); a listing of the words used in some enterprise
vocal cord - either of two pairs of folds of mucous membrane projecting into the larynx
vocational rehabilitation - providing training in a specific trade with the aim of gaining employment
voice - a means or agency by which something is expressed or communicated; the distinctive quality or pitch or condition of a person's speech; the ability to speak; the sound made by the vibration of vocal folds modified by the resonance of the vocal tract; something suggestive of speech in being a medium of expression; a sound suggestive of a vocal utterance; (metonymy) a singer; (linguistics) the grammatical relation (active or passive) of the grammatical subject of a verb to the action that the verb denotes; the melody carried by a particular voice or instrument in polyphonic music; expressing in coherent verbal form; an advocate who represents someone else's policy or purpose; verb give voice to; utter with vibrating vocal chords
volition - the act of making a choice; the capability of conscious choice and decision and intention
volt - a unit of potential equal to the potential difference between two points on a conductor carrying a current of 1 ampere when the power dissipated between the two points is 1 watt; equivalent to the potential difference across a resistance of 1 ohm when 1 ampere of current flows through it
volvulus - abnormal twisting of the intestines (usually in the are of the ileum or sigmoid colon) resulting in intestinal obstruction
vomiting - the reflex act of ejecting the contents of the stomach through the mouth
vomitus - the matter ejected in vomiting
voyeurism - a perversion in which a person receives sexual gratification from seeing the genitalia of others or witnessing others' sexual behavior
vulva - external parts of the female genitalia
vulvovaginitis - inflammation of the vulva and the vagina
wafer - thin disk of unleavened bread used in a religious service (especially in the celebration of the Eucharist); a small thin crisp cake or cookie; a small adhesive disk of paste; used to seal letters
wakefulness - a periodic state during which you are conscious and aware of the world; a temporary state in which you are unable (or unwilling) to sleep; the process of paying close and continuous attention
walker - an enclosing framework on casters or wheels; helps babies learn to walk; a light enclosing framework (trade name Zimmer) with rubber castors or wheels and handles; helps invalids or the handicapped or the aged to walk; a shoe designed for comfortable walking; United States writer (born in 1944); New Zealand runner who in 1975 became the first person to run a mile in less that 3 minutes and 50 seconds (born in 1952); a person who travels by foot
warfarin - an anticoagulant (trade name Coumadin) use to prevent and treat a thrombus or embolus
wart - (pathology) a firm abnormal elevated blemish on the skin; caused by a virus; any small rounded protuberance (as on certain plants or animals)
water supply - a facility that provides a source of water
water - a fluid necessary for the life of most animals and plants; binary compound that occurs at room temperature as a clear colorless odorless tasteless liquid; freezes into ice below 0 degrees centigrade and boils above 100 degrees centigrade; widely used as a solvent; once thought to be one of four elements composing the universe (Empedocles); a facility that provides a source of water; the part of the earth's surface covered with water (such as a river or lake or ocean); liquid excretory product; verb secrete or form water, as tears or saliva; supply with water, as with channels or ditches or streams; fill with tears; provide with water
watt - Scottish engineer and inventor whose improvements in the steam engine led to its wide use in industry (1736-1819); a unit of power equal to 1 joule per second; the power dissipated by a current of 1 ampere flowing across a resistance of 1 ohm
weakness - the property of lacking physical or mental strength; liability to failure under pressure or stress or strain; a penchant for something even though it might not be good for you; the condition of being financially weak; powerlessness revealed by an inability to act; a flaw or weak point
weaning - the act of substituting other food for the mother's milk in the diet of a child or young mammal
weber - German physiologist who studied sensory responses to stimuli and is considered the father of psychophysics (1795-1878); German conductor and composer of romantic operas (1786-1826); German sociologist and pioneer of the analytic method in sociology (1864-1920); United States abstract painter (born in Russia) (1881-1961); German physicist and brother of E. H. Weber; noted for his studies of terrestrial magnetism (1804-1891); a unit of magnetic flux equal to 100,000,000 maxwells
west nile virus - the flavivirus that causes West Nile encephalitis
wheezing - relating to breathing with a whistling sound
white matter - whitish nervous tissue of the CNS consisting of neurons and their myelin sheaths
williams syndrome - a rare congenital disorder associated with deletion of genetic material in chromosome 7; characterized by mental deficiency and some growth deficiency and elfin faces but an overly social personality and a remarkable gift for vocabulary
world health organization - a United Nations agency to coordinate international health activities and to help governments improve health services
wrist joint - a joint between the distal end of the radius and the proximal row of carpal bones
wrist - a joint between the distal end of the radius and the proximal row of carpal bones
x chromosome - the sex chromosome that is present in both sexes: singly in males and doubly in females
x-ray - a radiogram made by exposing photographic film to X rays; used in medical diagnosis; electromagnetic radiation of short wavelength produced when high-speed electrons strike a solid target; verb take an x-ray of something or somebody; examine by taking x-rays
xanthelasma - xanthoma of the eyelids; occurs chiefly in the elderly
xanthoma - a skin problem marked by the development (on the eyelids and neck and back) of irregular yellow nodules; sometimes attributable to disturbances of cholesterol metabolism
xanthomatosis - widespread xanthomas (especially on elbows and knees); often associated with a disorder of lipid metabolism
xanthomonas - a genus of bacteria similar to Pseudomonas but producing a yellow pigment that is not soluble in water
xenograft - tissue from an animal of one species used as a temporary graft (as in cases of severe burns) on an individual of another species
xenon - a colorless odorless inert gaseous element occurring in the earth's atmosphere in trace amounts
xenophobia - an irrational fear of foreigners or strangers
xeroderma pigmentosum - a rare genetic condition characterized by an eruption of exposed skin occurring in childhood and photosensitivity with severe sunburn; inherited as a recessive autosomal trait in which DNA repair processes are defective so they are more likely to chromosome breaks and cancers when exposed to ultraviolet light
xerophthalmia - abnormal dryness of the conjunctiva and cornea of the eyes; may be due to a systemic deficiency of vitamin A
xerostomia - abnormal dryness of the mouth resulting from decreased secretion of saliva
xylose - a sugar extracted from wood or straw; used in foods for diabetics
y chromosome - the sex chromosome that is carried by men
yawn - an involuntary intake of breath through a wide open mouth; usually triggered by fatigue or boredom; verb utter a yawn, as from lack of oxygen or when one is tired; be wide open
yaws - an infectious tropical disease resembling syphilis in its early stages; marked by red skin eruptions and ulcerating lesions
yeast - any of various single-celled fungi that reproduce asexually by budding or division; a commercial leavening agent containing yeast cells; used to raise the dough in making bread and for fermenting beer or whiskey
yellow fever - caused by a flavivirus transmitted by a mosquito
yersinia pestis - a bacillus bacterium that causes the plague; aerosolized bacteria can be used as a bioweapon
yolk sac - membranous structure enclosing the yolk of eggs in birds reptiles marsupials and some fishes; circulates nutrients to the developing embryo; membranous structure that functions as the circulatory system in mammal embryos until the heart becomes functional
ytterbium - a soft silvery metallic element; a rare earth of the lanthanide series; it occurs in gadolinite and monazite and xenotime
yttrium - a silvery metallic element that is common in rare-earth minerals; used in magnesium and aluminum alloys
zidovudine - an antiviral drug (trade name Retrovir) used in the treatment of AIDS; adverse side effects include liver damage and suppression of the bone marrow
zinc oxide - oxide of zinc; a white powder used as a pigment or in cosmetics or glass or inks and in zinc ointment
zinc sulfate - a colorless water-soluble powder; used as a mordant or to preserve wood or for the electrodeposition of zinc
zinc - a bluish-white lustrous metallic element; brittle at ordinary temperatures but malleable when heated; used in a wide variety of alloys and in galvanizing iron; it occurs as zinc sulphide in zinc blende; verb coat or cover with zinc
zingiber officinale - tropical Asian plant widely cultivated for its pungent root; source of gingerroot and powdered ginger
zirconium - a lustrous grey strong metallic element resembling titanium; it is used in nuclear reactors as a neutron absorber; it occurs in baddeleyite but is obtained chiefly from zircon
zoonosis - an animal disease that can be transmitted to humans
zoophobia - a morbid fear of animals
zygomatic bone - the arch of bone beneath the eye that forms the prominence of the cheek
zygote - the cell resulting from the union of an ovum and a spermatozoon (including the organism that develops from that cell)

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