Main Entry: an·trum

Pronunciation: \ˈan-trəm\

Function: noun

Inflected Form(s): plural an·tra \-trə\

Etymology: Late Latin, from Latin, cave, from Greek antron; akin to Armenian ayr cave

Date: circa 1751

: an anatomical cavity within a bone (as the maxilla) or hollow organ (as the stomach)

— an·tral \-trəl\ adjective