n, pl  apex*es  or  api*ces   :  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 .
 
 
 
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