c.1340, from O.Fr.
closet "small enclosure," dim. of
clos, from L.
clausum "closed space," from neut. pp. of
claudere "to shut" (see
close (v.)). In Matt. vi:6 used to render L.
cubiculum, Gk.
tamieion; originally in Eng. "a private room for study or prayer;" modern sense of "small side-room for storage" is first recorded 1616. The adjective meaning "secret, unknown" recorded from 1952, first of alcoholism, but by 1970s used principally of homosexuality; the phrase
come out of the closet "admit something openly" first recorded 1963, and led to new meanings for the word
out.