Main Entry: apex

Pronunciation: \ˈā-ˌpeks\

Function: noun

Inflected Form(s): plural apex·es or api·ces \ˈā-pə-ˌsēz\

: a narrowed or pointed end of an anatomical structure: as a : the narrow somewhat conical upper part of a lung extending into the root b : the lower pointed end of the heart situated in humans opposite the space between the cartilages of the fifth and sixth ribs on the left side c : the extremity of the root of a tooth