- abdomen, venter, stomach, belly - the region of the body of a vertebrate between the thorax and the pelvis
--1 is a kind of body part
--1 is a part of torso, trunk, body
--1 has parts: --1 has particulars: underbelly, underbody - abdominal cavity, abdomen - the cavity containing the major viscera; in mammals it is separated from the thorax by the diaphragm
--2 is a kind of cavity, bodily cavity, cavum
--2 is a part of abdomen, venter, stomach, belly