1186
Glossary
Articulation
The place of connection or junction
between two or more bones of a skeletal joint.
Ascites
An abnormal accumulation of serous fluid in
the peritoneal cavity.
Asepsis
The condition of being free or freed from
pathogenic microorganisms.
Astereognosis
A neurologic disorder characterized by
an inability to identify objects by touch.
Asterixis
A motor disturbance characterized by a hand-
flapping tremor, which results when the prolonged
contraction of groups of muscles lapses intermittently.
Ataxia
An abnormal condition characterized by an
inability to coordinate voluntary muscular movement.
Athetosis
A neuromuscular condition characterized by
the continuous occurrence of slow, sinuous, writhing
movements that are performed involuntarily.
(Adjective: athetoid)
Atopy
Genetic predisposition toward the development
of hypersensitivity or an allergic reaction to common
environmental allergens.
Atresia
The absence or closure of a normal body ori-
fice or tubular organ, such as the esophagus.
Atrophy
A wasting or diminution of size, often accom-
panied by a decrease in function, of a cell, tissue, or
organ.
Aura
A distinct subjective feeling, sensation, or motor
phenomenon that precedes and marks the onset of
an episode of a neurological condition, such as a
migraine or epileptic seizure.
Autocrine
A mode of hormone action in which a chem-
ical messenger acts on the same cell that secretes it.
Autophagy
Segregation of part of the cell’s own dam-
aged cytoplasmic material within a vacuole and its
disposal.
Autosome
Any chromosome other than a sex
chromosome.
Axillary
Of or pertaining to the axilla, or armpit.
Bacteremia
The presence of bacteria in the blood.
Bactericide
An agent that destroys bacteria. (Adjective:
bactericidal)
Bacteriostat
An agent that inhibits bacterial growth.
(Adjective: bacteriostatic)
Ballismus
An abnormal condition characterized by
violent flailing motions of the arms and, occasion-
ally, the head, resulting from injury to or destruction
of the subthalamic nucleus or its fiber connections.
Baroreceptor
A type of sensory nerve ending, such as
those found in the aorta and the carotid sinus, that
is stimulated by changes in pressure.
Basal
Pertaining to, situated at, or forming the base; or
the fundamental or basic.
Benign
Not malignant; or of the character that does
not threaten health or life.
Bipolar neuron
A nerve cell that has an afferent
process at one end and an efferent process at the
other end.
Bolus
A rounded mass of food ready to swallow or
such a mass passing through the gastrointestinal
tract; or a concentrated mass of medicinal material
or other pharmaceutical preparation injected all at
once intravenously for diagnostic purposes.
Borborygmus
The rumbling, gurgling, or tinkling noise
produced by the propulsion of gas through the intestine.
Bruit
A sound or murmur heard while auscultating an
organ or blood vessel, especially an abnormal one.
Buccal
Pertaining to or directed toward the inside of
the cheek.
Buffer
A substance or group of substances that
prevents change in the concentration of another
chemical substance.
Bulla
A thin-walled blister of the skin or mucous
membranes greater than 5 mm in diameter contain-
ing serous or seropurulent fluid.
Bursa
A fluid-filled sac or saclike cavity situated in
places in the tissues at which friction would other-
wise develop, such as between certain tendons and
the bones beneath them.
Cachexia
A condition of general ill health and malnu-
trition, marked by weakness and emaciation.
Calculus
A stony mass formed within body tissues,
usually composed of mineral salts.
Capsid
The protein shell that envelops and protects the
nucleic acid of a virus.
Carcinogen
Any substance or agent that causes the
development or increases the incidence of cancer.
Carpal
Of or pertaining to the carpus, or wrist.
Caseation
A form of tissue necrosis in which the tissue
is changed into a dry, amorphous mass resembling
crumbly cheese.
Catabolism
A metabolic process through which
living organisms break down complex substances
to simple compounds, liberating energy for use in
work, energy storage, or heat production.
Catalyst
A substance that increases the velocity of a
chemical reaction without being consumed by the
process.
Catecholamines
Any one of a group of biogenic
amines having a sympathomimetic action and
composed of a catechol molecule and the aliphatic
portion of an amine.
Caudal
Signifying an inferior position, toward the
distal end of the spine.
Cellulitis
An acute, diffuse, spreading, edematous
inflammation of the deep subcutaneous tissues and
sometimes muscle, characterized most commonly
by an area of heat, redness, pain, and swelling, and
occasionally by fever, malaise, chills, and headache.
Cephalic
Of or pertaining to the head, or to the head
end of the body.
Cerumen
The waxlike secretion produced by vestigial
apocrine sweat glands in the external ear canal.
Cheilosis
A noninflammatory disorder of the lips and
mouth characterized by chapping and fissuring.
Chelate
A chemical compound composed of a central
metal ion and an organic molecule with multiple
bonds, arranged in ring formation, used especially in
treatment of metal poisoning.
Chemoreceptor
A sensory nerve cell activated by
chemical stimuli; for example, a chemoreceptor
in the carotid artery is sensitive to changes in the
oxygen content in the blood and reflexly increases or
decreases respiration and blood pressure.
