Main Entry: on·tol·o·gy

Pronunciation: \än-ˈtä-lə-jē\

Function: noun

Etymology: New Latin ontologia, from ont- + -logia -logy

Date: circa 1721

1 : a branch of metaphysics concerned with the nature and relations of being
2 : a particular theory about the nature of being or the kinds of things that have existence

— on·tol·o·gist \-jist\ noun