epiphany (n.)

early 14c., "festival of the manifestation of Christ to the gentiles" (celebrated Jan. 6; usually with a capital -E-), from Old French epiphanie, from Late Latin epiphania, neuter plural (taken as feminine singular), from late Greek epiphaneia "manifestation, striking appearance, festival held in commemoration of the appearance of a god at some particular place" (in New Testament, "advent or manifestation of Christ"), from epiphanes "manifest, conspicuous," from epiphainein "to manifest, display, show off; come suddenly into view," from epi "on, to" (see epi-) + phainein "to show" (from PIE root *bha- (1) "to shine"). Of divine beings other than Christ, first recorded 1660s; general literary sense of "any manifestation or revelation" appeared 1840, first in De Quincey.