Abdomen

First attested in 1541.

Borrowing from frm abdomen, Borrowing from la abdomen, possibly from abdÅ ("conceal"), from ab ("away") + dere ("to put, place").

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Full definition of abdomen

(plural abdomens or abdomina)

(obsolete) The fat surrounding the belly. Attested from the mid 16^th century until the late 17^th century.

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(anatomy) The belly, or that part of the body between the thorax and the pelvis, not including the back; or in some lower vertebrates, the portion between the cardiac and caudal regions. First attested in the early 17^th century.
(anatomy) The cavity of the belly, which is lined by the peritoneum, and contains the viscera; often restricted in humans to the part between the diaphragm and the commencement of the pelvis, the remainder being called the pelvic cavity. First attested in the early 17^th century.He was all bent over complaining of pains in the abdomen.
(zoology, entomology) The posterior section of the body, behind the thorax, in insects, crustaceans, and other Arthropoda. First attested in the late 18^th century.