apophthegm (n.)

"short, pithy, instructive saying," 1550s, from Greek apophthegma "terse, pointed saying," literally "something clearly spoken," from apophthengesthai "to speak one's opinion plainly," from apo "from" (see apo-) + phthengesthai "to utter" (see diphthong). See aphorism for nuances of usage. The spelling apophthegm, restored by Johnson, is "now more frequent in England," according to OED (1989). Related: Apothegmatic.