Copy of `Dorland's Medical Dictionary`

The wordlist doesn't exist anymore, or, the website doesn't exist anymore. On this page you can find a copy of the original information. The information may have been taken offline because it is outdated.

Dorland's Medical Dictionary Category: Health and Medicine > Medical Dictionary Date & country: 31/12/2010, USA Words: 39128

aborad
(ab-or´ad) away from the mouth.

aboral
(ab-or´әl) opposite to, or remote from, the mouth.

abort
(ә-bort´) to arrest prematurely a disease or developmental process; to expel the products of conception before the fetus is viable.

abortifacient
(ә-bor″tĭ-fa´shәnt) causing abortion. an agent that induces abortion.

abortion
(ә-bor´shәn) termination of pregnancy before the fetus is viable. In the medical sense, this term and the term miscarriage are synonyms; both refer to the termination of pregnancy before the fetus is capable of survival outside the uterus. The term abortion is popularly used as a synonym for induced abortion...

abortive
(ә-bor´tiv) incompletely developed. abortifacient. cutting short the course of a disease.

abortive poliomyelitis
the minor illness of poliomyelitis; see poliomyelitis.

abortus
(ә-bor´tәs) a dead fetus or one that is nonviable (defined as one weighing less than 500 g at birth).

above-elbow (A-E) amputation
amputation of the upper limb between the elbow and the shoulder.

above-knee (A-K) amputation
transfemoral amputation.

ABR
auditory brainstem response.

abrachia
(ә-bra´ke-ә) a developmental anomaly consisting of absence of the arms.

abrachiocephalia
(ә-bra″ke-o-sĕ-fa´le-ә) acephalobrachia.

Abrams heart reflex
contraction of the myocardium, with reduction in the area of cardiac dullness, which results when the skin of the precordial region is irritated. It is observed with the fluoroscope.

abrasion
(ә-bra´zhәn) the wearing away of a substance or structure, such as the skin or teeth, through some unusual or abnormal process. a wound caused by rubbing or scraping the skin or a mucous membrane; a “skinned knee” and a “floor burn” are common examples. To treat the inju...

abrasion layer
a protective covering of gelatin enclosing an emulsion on x-ray film; called also overcoat.

abrasive
(ә-bra´siv) causing abrasion. an agent that produces abrasion.

abreaction
(ab″re-ak´shәn) the expression of emotions associated with repressed material, usually of an anxiety-provoking or conflictual nature, which is brought into a person's awareness and relived. See also catharsis.

Abrikosov (Abrikossoff) tumor
granular cell tumor.

abruptio
(ab-rup´she-o) Latin word meaning separation. abruptio placentae premature separation of a normally situated but improperly implanted placenta; it usually occurs late in pregnancy, but may take place during labor. Separation of the placenta before the 24th week of pregnancy is co...

abscess
(ab´ses) a localized collection of pus in a cavity formed by the disintegration of tissue, usually caused by microorganisms that invade the tissues, such as through a small wound or break in the skin. An abscess is a natural defense mechanism in which the body attempts to localize an infection and wall off the mic...

abscissa
(ab-sis´ә) the horizontal line in a graph along which are plotted the units of one of the variables considered in the study, as time in a time-temperature study. The other line is called the ordinate.

abscission
(ab-sĭ´zhәn) removal by cutting.

abscopal
(ab-sko´pәl) pertaining to the effect on nonirradiated tissue resulting from irradiation of other tissues of the body.

absence epilepsy
a mild type of epilepsy in which the person loses consciousness for just a short time, in contrast to grand mal epilepsy; called also petit mal epilepsy.

absence seizure
the seizure seen in absence epilepsy, marked by a momentary break in the stream of thought and activity, accompanied by a symmetrical spike and wave at 3 cycles per second on the electroencephalogram.

absence status
sustained clouding of consciousness for several hours, with no interval of normal mental activity, and with few stereotyped movements or no abnormal motor activity.

Absettarov virus
a strain of Central European encephalitis virus belonging to the Far Eastern subgroup of the tick-borne encephalitis viruses, which causes disease in Central Europe, Scandinavia, and the western part of the former Soviet Union.

Absidia
(ab-sid´e-ә) a genus of perfect fungi; the species A. ramo´sa is found on decaying plants and baked goods and can cause mucormycosis.

absolute
(ab´sә-lldbomact) free from limitations; unlimited; uncombined.

absolute accommodation
the accommodation of either eye separately.

absolute alcohol
dehydrated alcohol.

absolute near point
the near point for either eye alone with accommodation relaxed.

absolute polycythemia
an increase in red blood cell mass because of sustained overactivity of the red cell-producing components of the bone marrow; this may occur as a physiologic response compensating for hypoxia of the tissues (see secondary polycythemia), or as the principal manifestation of polycythemia vera. See also relative polycythemia.

absolute refractory period
the part of the refractory period from phase 0 to approximately −60 mV during phase 3; during this time it is impossible for the myocardium to respond with a propagated action potential, even with a strong stimulus. Called also effective refractory period.

absolute scale
absolute temperature scale one with its zero at absolute zero (−273.15°C, −459.67°F). Kelvin scale.

absolute scotoma
an area within the visual field in which perception of light is entirely lost.

absolute temperature
(T) that reckoned from absolute zero (−273.15°C), expressed on an absolute scale.

absorb
(ab-sorb´) to take in or assimilate, as to take up substances into or across tissues, such as the skin or intestine. to stop particles of radiation energy so that their energy is totally transferred to the absorbing material. to retain specific wavelengths of radiation incident upon a substance, ei...

absorbable
(ab-sorb´ә-bәl) capable of being absorbed.

absorbable surgical suture
a sterile absorbable suture made of collagen derived from healthy mammals or from a synthetic polymer, available in various diameters and tensile strengths; it may be treated to modify its resistance to absorption, impregnated with a suitable antimicrobial agent, and colored.

absorbable suture
a strand of material that is used for closing wounds and becomes dissolved in the body fluids and disappears; types include surgical gut, tendon, and some synthetics.

absorbance
(ab-sor´bәns) in radiology, a measure of the ability of a medium to absorb radiation, expressed as the logarithm of the quotient of the intensity of the radiation entering the medium divided by that leaving it. Called also optical density.

absorbed dose
the amount of energy from ionizing radiation absorbed per unit mass of matter, expressed in rads.

absorbefacient
(ab-sor″bә-fa´shәnt) causing absorption. absorbent (def. 3).

absorbent
(ab-sor´bәnt) able to take in, or suck up and incorporate. a tissue structure involved in absorption. a substance that absorbs or promotes absorption.

absorbent point
in root canal therapy, a cone of variable width and taper, usually made of paper or a paper product, used to dry or maintain a liquid disinfectant in the canal. Called also paper point.

absorbent vessel
lymphatic vessel.

absorptiometry
(ab-sorp″she-om´ә-tre) in radiology, the measurement of the degree to which the radiation emitted by a radioisotope is completely dissipated within a tissue. dual energy x-ray absorptiometry(DEXA) an imaging technique that uses two low-dose x-ray beams ...

absorption
(ab-sorp´shәn) the act of taking up or in by specific chemical or molecular action, such as in chemical absorption or digestive absorption. in psychology, devotion of thought to one object or activity only. radiation absorption. in chemistry, the penetration of a substance withi...

absorption atelectasis
that produced by any factor (such as secretions, foreign body, tumor, or abnormal external pressure) that completely obstructs the airway, preventing intake of air into the alveolar sacs and permitting absorption of air into the bloodstream. Called also obstructive or secondary atelectasis.

absorption cavities
cavities in developing compact bone due to osteoclastic erosion, usually occurring in the areas laid down first.

absorption coefficient
absorptivity. linear absorption coefficient. mass absorption coefficient.

absorption lacuna
resorption lacuna.

absorption lines
dark lines in the spectrum due to absorption of light by the substance through which the light has passed.

absorptive
(ab-sorp´tiv) having the power of absorption; involving absorption.

absorptivity
(ab″sorp-tiv´ĭ-te) a measure of the amount of light absorbed by a solution.

abstergent
(ab-stur´jәnt) cleansing or detergent. a cleansing agent.

abstinence
(ab´sti-nәns) a refraining from the use of or indulgence in food, stimulants, or coitus. periodic abstinence natural family planning; see contraception.

abstinence syndrome
withdrawal (def. 3).

abstraction
(ab-strak´shәn) the mental process of forming ideas that are theoretical or representational rather than concrete. the withdrawal of any ingredient from a compound. malocclusion in which the occlusal plane is farther from the eye-ear plane, causing lengthening of the face.

abulia
(ә-boo´le-ә) lack of will or willpower; inability to make decisions. adj. abu´lic., adj. akinetic mutism.

abuse
(ә-būs´) misuse, maltreatment, or excessive use.

abutment
(ә-but´mәnt) a part of a structure that sustains thrust or pressure. a tooth or root that serves as anchorage for a bridge.

abutment tooth
one chosen to support a bridge; see abutment.

Ac
actinium.

acalculia
(a″kal-ku´le-ә) inability to solve mathematical calculations.

acalculous cholecystitis
any cholecystitis that is not caused by gallstones. These types constitute a minority of cases but usually have a much more grave prognosis than calculous cholecystitis because there may be serious complications such as gangrene and perforation. Acalculous types are usually secondary to bile duct obstruction and stasis of bile,...

acampsia
(ә-kamp´se-ә) rigidity of a part or limb.

acantha
(ә-kan´thә) spine (def. 1). spinous process of vertebra.

acanthamebiasis
(ә-kan″thә-me-bi´ә-sis) infection with Acanthamoeba castellani.

Acanthamoeba
(ә-kan″thә-me´bә) a genus of free-living ameboid protozoa found usually in fresh water or moist soil. Certain species, such as A. castella´ni, A. poly´phaga, A. astronyx´is, and A. culbert´soni, may occur as opportunistic human pathogens, causing an acute fatal or chronic infection of the eye, brain, l...

Acanthamoeba
keratitis amebic keratitis due to infection by Acanthamoeba species, usually associated with soft contact lens wear, particularly overnight wear.

acanthesthesia
(ә-kan″thes-the´zhә) a sensation of a sharp point pricking the body.

acanthion
(ә-kan´the-on) a point at the tip of the anterior nasal spine.

Acanthocephala
(ә-kan″tho-sef´ә-lә) a phylum of elongate, mostly cylindrical organisms (thorny headed worms) parasitic in the intestines of all classes of vertebrates.

acanthocephaliasis
(ә-kan″tho-sef″ә-li´ә-sis) infection with worms of the phylum Acanthocephala.

acanthocyte
(ә-kan´tho-sīt) a erythrocyte with small spikes on the surface, of normal or slightly reduced size, seen in congenital abetalipoproteinemia, cirrhosis, hemolytic anemia, hepatitis of the newborn, vitamin E deficiency, and hypercholesterolemia. Called also spur cell.

acanthocytosis
(ә-kan″tho-si-to´sis) the presence in the blood of acanthocytes.

acantholysis
(ak″an-thol´ĭ-sis) disruption of the intercellular connections between keratinocytes of the epidermis, caused by lysis of intercellular cement substance. It is associated with the formation of epidermal vesicles in such conditions as pemphigus vulgaris, pemphigus foliaceus, and other skin disorders.

acanthoma
(ak″an-tho´mә) pl. acanthomas, acantho´mata a tumor in the prickle cell layer of the skin.

Acanthophis
(ә-kan´tho-fis) a genus of snakes of the family Elapidae. A. antarc´ticus is the death adder of Australia and New Guinea.

acanthosis
(ak″an-tho´sis) diffuse hypertrophy or thickening of the prickle cell layer of the skin. adj., acanthot´ic., adj. acanthosis nigricans diffuse acanthosis with gray, brown, or black pigmentation, chiefly in the armpits and other body folds. In adults, one form (mali...

acanthrocytosis
(ә-kan″thro-si-to´sis) acanthocytosis.

acarbose
(a´kahr-bōs) an α-glucosidase inhibitor used to combat hyperglycemia in treatment of type 2 diabetes mellitus.

acardia
(a-kahr´de-ә) a developmental anomaly consisting of absence of the heart.

acardiacus
(a″kahr-di´ә-kus) Latin word meaning having no heart.

acardius
(a-kahr´de-әs) a parasitic twin fetus that lacks a heart and uses the circulation of its twin. See also hemiacardius and holoacardius.

acariasis
(ak″ә-ri´ә-sis) infestation with mites.

acaricide
(ә-kar´ĭ-sīd) an agent that destroys mites.

acarid
(ak´ә-rid) a tick or a mite of the order Acarina.

acaridiasis
(ә-kar″ĭ-di´ә-sis) acariasis.

Acarina
(ak″ә-ri´nә) an order of arthropods (class Arachnoidea), including mites and ticks.

acarinosis
(ә-kar″ĭ-no´sis) any disease caused by mites; acariasis.

acarodermatitis
(ak″ә-ro-dur″mә-ti´tis) skin inflammation due to bites of parasitic mites (acarids).

acarology
(ak″ә-rol´ә-je) the scientific study of mites and ticks.

acarophobia
(ak″ә-ro-fo´be-ә) irrational fear of mites or of other minute objects, which may be animate (insects, worms) or inanimate (pins, needles). Sometimes there is also a fear of parasites crawling beneath the skin.

Acarus
(ak´ә-rәs) a genus of small mites that can cause itch, mange, and other skin diseases. Several species live on plants used as food by humans and burrow under the skin of persons handling them.

acatalasemia
(a″kat-ә-la-se´me-ә) acatalasia.

acatalasia
(a″kat-ә-la´zhә) a rare hereditary disease seen mostly in Japan and Switzerland, marked by congenital absence of catalase; it may be asymptomatic but is usually associated with recurrent infections of oral structures. A variety in Japan is characterized by oral ulcerations and gangrene and is kno...