1560s, from Late Latin, from Greek, literally "the latter (put as) the former." A figure of speech in which what should come last is put first, from hysteron, neuter of hysteros "latter, second, after" (from PIE *ud-tero-, from root *ud- "up, out;" see out) + proteron, neuter of proteros "before, former," from PIE *pro-, from root *per- (1) "forward, through" (see per).