Webster's New World Medical Dictionary

abdomen, acute
See 
acute abdomen.
abdominal aorta
The final section of the aorta,
the largest artery in the body, which begins at the
diaphragm as a continuation of the thoracic aorta
and ends by splitting in two, to form the common
iliac arteries. The abdominal aorta supplies oxy-
genated blood to all the abdominal and pelvic
organs, as well as to the legs. See also 
aorta.
abdominal aortic aneurysm
See 
aneurysm,
abdominal aortic.
abdominal cavity
The cavity within the
abdomen. This space between the abdominal wall
and the spine contains a number of crucial organs,
including the lower part of the esophagus, the stom-
ach, small intestine, colon, rectum, liver, gallblad-
der, pancreas, spleen, kidneys, adrenal glands,
ureters, and bladder. See also 
abdomen.
abdominal guarding
Tensing of the abdominal
wall muscles to guard inflamed organs within the
abdomen from the pain of pressure upon them.
Abdominal guarding is detected when the abdomen
is pressed and is an indication that inflammation of
the inner abdominal (peritoneal) surface may be
present due, for example, to appendicitis or diverti-
culitis. The tensed muscles of the abdominal wall
automatically go into spasm to keep the tender
underlying tissues from being irritated.
abdominal hysterectomy
See 
hysterectomy,
abdominal.
abdominal muscle
One of a large group of mus-
cles in the front of the abdomen that assists in main-
taining regular breathing movements, supports the
muscles of the spine while lifting, and keeps abdom-
inal organs in place. Abdominal muscles are the tar-
get of many exercises, such as sit-ups. Abdominal
muscles are informally known as the abs.
abdominal pain
Pain in the belly. Abdominal
pain can be acute or chronic. It may reflect a major
problem with one of the organs in the abdomen,
such as appendicitis or a perforated intestine, or it
may result from a fairly minor problem, such as
excess buildup of intestinal gas.