1650s, "harsh or unpleasant sound," probably via French cacophonie (16c.), from a Latinized form of Greek kakophonia, from kakophonos "harsh sounding," from kakos "bad, evil" (from PIE root *kakka- "to defecate") + phone "voice, sound," from PIE root *bha- (2) "to speak, tell, say." Meaning "discordant sounds in music" is from 1789. Related: Cacophonous.