late 14c., "western part" (of the heavens or earth), from Old French occident (12c.) or directly from Latin occidentem (nominative occidens) "western sky, sunset, part of the sky in which the sun sets," noun use of adjective meaning "setting," from present participle of occidere "fall down, go down" (see occasion (n.)).[Occident etymology, Occident origin, 英语词源]