Medical Dictionary banner
Medical Dictionary - Dictionary of Medicine and Human Biology

Medical Dictionary


bioactive (bi′o-ak′tiv)
Referring to a substance that can be acted upon by a living organism or by an extract from a living organism.

bioassay (bi-o-as′a)
Determination of the potency or concentration of a compound by its effect upon animals, isolated tissues, or microorganisms, as compared with an analysis of its chemical or physical properties.

bioastronautics (bi′o-as-tro-naw′tiks)
The study of the effects of space travel and space habitation on living organisms.

bioavailability (bi′o-a-val′a-bil′i-te)
The physiological availability of a given amount of a drug, as distinct from its chemical potency; proportion of the administered dose which is absorbed into the bloodstream.

bioburden (bi′o-ber′den)
Degree of microbial contamination or microbial load; the number of microorganisms contaminating an object.

biocatalyst (bi′o-kat-a-list)
A substance of biologic origin that can catalyze a reaction; e.g., an enzyme.

biocenosis (bi-o-se-no′sis)
An assemblage of species living in a particular biotope. SYN: biotic community. [bio- + G. koinos, common]

biochemical (bi-o-kem′i-kal)
Relating to biochemistry.

biochemistry (bi-o-kem′is-tre)
The chemistry of living organisms and of the chemical, molecular, and physical changes occurring therein. SYN: biologic chemistry, physiologic chemistry.

biochemorphic (bi′o-kem-or′fik)
Denoting the relationship between biologic action and chemical structure, as in food and drugs.

biochrome (bi′o-krom)
SYN: natural pigment. [bio- + G. chroma, color]

biocidal (bi-o-si′dal)
Destructive of life; particularly pertaining to microorganisms. [bio- + L. caedo, to kill]

bioclimatology (bi′o-kli-ma-tol′o-je)
The science of the relationship of climatic factors to the distribution, numbers, and types of living organisms; an aspect of ecology.

biocompatibility (bi′o-kom-pat-i-bil′i-te)
The relative ability of a material to interact favorably with a biological system. [bio- + compatibility]

biocybernetics (bi′o-si-ber-net′iks)
The science of communication and control within a living organism, particularly on a molecular basis.

biocytin (bi-o-si′tin)
ε-N-Biotinyl-l-lysine;biotin condensed through its carboxyl group with the ε-amino group of a lysyl residue in the apoenzymes to which biotin is the coenzyme; the predominant linkage in which biotin is found. SYN: biotinyllysine.

biocytinase (bi-o-si′tin-as)
An enzyme in blood that catalyzes the hydrolysis of biocytin to biotin and lysine (or, lysyl residue if the lysine is in a protein).

biodegradable (bi′o-de-grad′a-bl)
Denoting a substance that can be chemically degraded or decomposed by natural effectors ( e.g., weather, soil bacteria, plants, animals).

SYN: biotransformation.

biodynamic (bi′o-di-nam′ik)
Relating to biodynamics.

biodynamics (bi′o-di-nam′iks)
The science dealing with the force or energy of living matter. [bio- + G. dynamis, force]

bioecology (bi-o-e-kol′o-je)
SYN: ecology.

bioelement (bi′o-el′e-ment)
An element required by a living organism.

bioenergetics (bi′o-en-er-jet′iks)
1. The study of energy changes involved in the chemical reactions within living tissue. 2. The study of energy exchanges between living organisms and their environments.

bioengineering (bi′o-en-jin-er′ing)
See biomedical engineering.

biofeedback (bi-o-fed′bak)
A training technique that enables an individual to gain some element of voluntary control over autonomic body functions; based on the learning principle that a desired response is learned when received information such as a recorded increase in skin temperature (feedback) indicates that a specific thought complex or action has produced the desired physiological response. EMG b. a form of b. that uses an electromyographic measure of muscle tension as the physical symptom to be deconditioned, such as tension in the frontalis muscle in the head which can cause headaches.

bioflavonoids (bi-o-flav′on-oydz)
Naturally occurring flavone or coumarin derivatives commonly found in citrus fruits having the activity of the so-called vitamin P, notably rutin and esculin.

biogenesis (bi-o-jen′e-sis)
1. Term given by Huxley to the principle that life originates from preexisting life only and never from nonliving material. See spontaneous generation, recapitulation theory. 2. SYN: biosynthesis. [bio- + G. genesis, origin] mitochondrial b. the process by which mitochondria increase their ability to make adenosine triphosphate by synthesizing additional respiratory enzyme complexes.

biogenetic (bi′o-je-net′ik)
Relating to biogenesis.

biogenic (bi′o-jen-ik)
Produced by a living organism.

biogeochemistry (bi′o-je-o-kem′is-tre)
The study of the influence of living organisms and life processes on the chemical structure and history of the earth.

biogravics (bi-o-grav′iks)
That field of study dealing with the effect on living organisms (particularly humans) of abnormal gravitational effects produced, e.g., by acceleration or by free fall; in the former case, heavier than normal weight is induced, and in the latter weightlessness. [bio- + L. gravis, weight]

A scientific discipline encompassing all aspects of biologic information acquisition, processing, storage, distribution, analysis, and interpretation that combines the tools and techniques of mathematics, computer science, and biology with the aim of understanding the biologic significance of a variety of data.

bioinstrument (bi′o-in′stroo-ment)
A sensor or device usually attached to or embedded in the human body or other living animal to record and to transmit physiologic data to a receiving and monitoring station.

biokinetics (bi′o-ki-net′iks)
The study of the growth changes and movements that developing organisms undergo. [bio- + G. kinesis, motion]

biologic, biological (bi′o-loj′ik, -loj′i-kal)
Relating to biology.

biologist (bi-ol′o-jist)
A specialist or expert in biology.

biology (bi-ol′o-je)
The science concerned with the phenomena of life and living organisms. [bio- + G. logos, study] cellular b. SYN: cytology. molecular b. study of phenomena in terms of b. molecular (or chemical) interactions; traditionally, the focus of molecular b. is more specific than biochemistry in that it has an emphasis on chemical interactions involved in the replication of DNA, its “transcription” into RNA, and its “translation” into or expression in protein, i.e., in the chemical reactions connecting genotype and phenotype. oral b. that aspect of b. devoted to the study of biological phenomena associated with the oral cavity in health and disease ( e.g., dental caries, mastication, periodontal disease). pharmaceutical b. SYN: pharmacognosy. radiation b. field of science that studies the biological effects of ionizing radiation.

bioluminescence (bi′o-loo-min-es′ens)
1. Light produced by certain organisms from the oxidation of luciferins through the action of luciferases and with negligible production of heat, chemical energy being converted directly into light energy. SYN: cold light (1) . 2. Any light produced by a living organism. [bio- + L. lumen (-inis), light]

biolysis (bi-ol′i-sis)
Disintegration of organic matter through the chemical action of living organisms. [bio- + G. lysis, dissolution]

biolytic (bi-o-lit′ik)
1. Relating to biolysis. 2. Capable of destroying life.

biomacromolecule (bi′o-mak-ro-mol′e-kul)
A naturally occurring substance of large molecular weight ( E.G., protein, DNA).

biomass (bi′o-mas)
The total weight of all living things in a given area, biotic community, species population, or habitat; a measure of total biotic productivity.

biomaterial (bi′o-ma-te′re-al)
A synthetic or semisynthetic material used in a biological system to construct an implantable prosthesis and chosen for its biocompatibility. [bio- + material]

biome (bi′om)
The total complex of biotic communities occupying and characterizing a particular geographic area or zone. [bio- + -ome]

biomechanics (bi-o-me-kan′iks)
The science concerned with the action of forces, internal or external, on the living body. dental b. SYN: dental biophysics.

biomedical (bi-o-med′i-kal)
1. Pertaining to those aspects of the natural sciences, especially the biologic and physiologic sciences, that relate to or underlie medicine. 2. Biological and medical, i.e., encompassing both the science(s) and the art of medicine.

biomembrane (bi-o-mem′bran)
A structure bounding a cell or cell organelle; it contains lipids, proteins, glycolipids, steroids, etc. SYN: membrane (2) .

biometer (bi-om′e-ter)
A device for measuring carbon dioxide given off by organisms and, hence, for determining the quantity of living matter present. [bio- + G. metron, measure]

biometrician (bi-o-me-trish′an)
One who specializes in the science of biometry.

biometry (bi-om′e-tre)
The application of statistical methods to the study of numeric data based on biologic observations and phenomena. [bio- + G. metron, measure] b. fetal ultrasound measurement of fetal dimensions to evaluate gestational age of fetal size.

biomicroscope (bi-o-mi′kro-skop)
SYN: slitlamp.

biomicroscopy (bi′o-mi-kros′ko-pe)
1. Microscopic examination of living tissue in the body. 2. Examination of the cornea, aqueous humor, lens, vitreous humor, and retina by use of a slitlamp combined with a binocular microscope.

Biomphalaria (bi-om-fa-la′re-a)
An important genus of freshwater snails (family Planorbidae, subfamily Planorbinae), several species of which serve as intermediate hosts of Schistosoma mansoni in Africa, Saudi Arabia and Yemen, South America, and the Caribbean. Host snails formerly were placed in the genera Australorbis, Tropicorbis, and Taphius but are no longer considered generically distinct.

bion (bi′on)
A living thing. [G. pres. p. ntr. of bioo, to live]

Aldolpho, Italian pathologist, 1846–1917. See B.-Heidenhain stain.

bionecrosis (bi-o-ne-kro′sis)

bionic (bi-on′ik)
Relating to or developed from bionics.

bionics (bi-on′iks)
1. The science of biologic functions and mechanisms as applied to electronic chemistry; such as computers, employing various aspects of physics, mathematics, and chemistry; e.g., improving cybernetic engineering by reference to the organization of the vertebrate nervous system. 2. The science of applying the knowledge gained by studying the characteristics of living organisms to the formulation of nonorganic devices and techniques. [bio- + electronics]

bionomics (bi-o-nom′iks)
1. SYN: bionomy. 2. SYN: ecology.

bionomy (bi-on′o-me)
The laws of life; the science concerned with the laws regulating the vital functions. SYN: bionomics (1) . [bio- + G. nomos, law]

biophage (bi′o-faj)
An organism that derives the nourishment for its existence from another living organism.

biophagism (bi-of′a-jizm)
The deriving of nourishment from living organisms. SYN: biophagy. [bio- + G. phago, to eat]

biophagous (bi-of′a-gus)
Feeding on living organisms; denoting certain parasites.

biophagy (bi-of′a-je)
SYN: biophagism.

biopharmaceutics (bi′o-far-ma-soo′tiks)
The study of the physical and chemical properties of a drug, and its dosage form, as related to the onset, duration, and intensity of drug action, incluidng co-constituents and mode of manufacture.

biophylactic (bi′o-fi-lak′tik)
Relating to biophylaxis.

biophylaxis (bi′o-fi-lak′sis)
Nonspecific defense reactions of the body, e.g., phagocytosis, vascular and other reactions of inflammatory processes. [bio- + G. phylaxis, protection]

biophysics (bi-o-phyz′iks)
1. The study of biologic processes and materials by means of the theories and tools of physics; the application of physical methods to analyze biologic problems and processes. 2. The study of physical processes ( e.g., electricity, luminescence) occurring in organisms. cellular b. b. concerned with cellular processes. dental b. the relationship between the biologic behavior of oral structures and the physical influence of a dental restoration. SYN: dental biomechanics. medical b. b. related to diagnosis and therapy. molecular b. b. concerned with membrane processes, conformational and configurational properties of macromolecules, bioelectrical phenomena, etc. radiation b. the study of the effects of radiation on cells, tissues, biomolecules, and living organisms.

bioplasm (bi′o-plazm)
Protoplasm, especially in its relation to living processes and development. [bio- + G. plasma, thing formed]


. . . Feedback