Medical Dictionary Definitions A-Z List
Medical Dictionary Definitions A - Z - «A»:
Abdominal aortic aneurysm
Abdominal aortic aneurysm: A ballooning or widening of the main artery (the aorta) as it courses down through the abdomen. At the point of the
aneurysm, the aneurysm usually measures 3 cm or more in
diameter. The aneurysm weakens the wall of the aorta and
can end in the aorta rupturing with cata...
Abdominal cavity: The cavity within the abdomen, the
space between the abdominal wall and the spine.
The abdominal cavity is hardly an empty space. It contains a
number of crucial organs including the lower part of the esophagus,
the stomach, small intestine, colon, rectum, liver, gallbladder, ...
Abdominal guarding: Tensing of the abdominal wall muscles to
guard inflamed organs within the abdomen from the pain of pressure
upon them. The tensing is detected when the abdomen wall is
Guarding is a characteristic finding in the physical examination for
an abruptly painful abdomen (a...
Abdominal hysterectomy: Surgical removal of
the uterus (a hysterectomy) done
through an incision made in the abdominal wall. As opposed to a
vaginal hysterectomy in which the incision is made within the
Abdominal muscle deficiency syndrome
Abdominal muscle deficiency syndrome: Partial or complete absence of the abdominal muscles so that the outlines of the intestines are visible through the thin, lax, protruding abdominal wall. Also called the "prune belly syndrome." The full syndrome probably occurs only in males. In addition to the ...
Abdominal muscles: A large group of muscles
in the front of the
abdomen that assists in the regular breathing movement and supports
the muscles of the
spine while lifting and keeping abdominal organs such as the
intestines in place. Abdominal muscles play a key role in exercises
such as "sit-ups...
Abdominal pain: Pain in the belly (the abdomen). Abdominal pain can come from conditions affecting a variety of organs. The abdomen is an anatomical area that is bounded by the lower margin of the ribs above, the pelvic bone (pubic ramus) below, and the flanks on each side. Although abdominal pain c...
Abducent nerve: A small motor nerve that has one task: to
supply a muscle called the lateral rectus muscle that moves the eye
Paralysis of the abducent nerve causes inward turning of the eye
(internal strabismus) leading to double vision.
The abducent nerve is the sixth cranial nerve. A...
Abduction: In medicine, the movement of a limb away from the midline of the body. Abduction of both legs spreads the legs. The opposite of abduction is adduction. Adduction of the legs brings them together.
From the Latin "ab-" meaning "away from" +
"ducere" meaning "to draw or lead" = "to draw awa...
Abductor muscle: Any muscle used to pull a
body part away from the midline of the body. For example, the
abductor muscles of the legs spread the legs away from the midline
and away from one another.
The word "abductor" comes from the Latin prefix "ab-" meaning "away from" + "ducere" meaning "to d...
Abductor spasmodic dysphonia
Abductor spasmodic dysphonia: A disorder in which sudden muscle spasms cause the vocal folds (or vocal cords) to stay open. See: spasmodic dysphonia....
Aberration: (1) A deviation or
irregularity. For example, a chromosome aberration is a deviation
from the normal chromosome number or the normal chromosome structure.
In this sense,
aberration is also synonymous with deflection, departure, divergence,
diversion, turning. (2) A mental aberration...
ABG (arterial blood gas)
ABG (arterial blood gas): The sampling of the blood levels of oxygen and carbon dioxide within the arteries, as opposed to the levels of oxygen and carbon dioxide in venous blood. Typically, the acidity, or pH, of the blood is measured simultaneously in ABG sampling....
Abiological: See: Abiotic....
Abiotic: 1. Not associated with living organisms.2. Anything in the environment incapable of life, such as the soil or weather.3. Incompatible with life or antagonist to it.
Also called abiological....