"to blame, reproach, taunt, upbraid," 1520s, twite, shortened form of Middle English atwite, from Old English ætwitan "to blame, reproach," from æt "at" + witan "to blame," from Proto-Germanic *witanan (cognates: Old English wite, Old Saxon witi, Old Norse viti "punishment, torture;" Old High German wizzi "punishment," wizan "to punish;" Dutch verwijten, Old High German firwizan, German verweisen "to reproach, reprove," Gothic fraweitan "to avenge"), from PIE root *weid- "to see" (see vision). For sense evolution, compare Latin animadvertere, literally "to give heed to, observe," later "to chastise, censure, punish." Related: Twitted; twitting. As a noun meaning "a taunt" from 1520s.

"foolish, stupid and ineffectual person," 1934, British slang, popular 1950s-60s, crossed over to U.S. with British sitcoms. It probably developed from twit, v. in the sense of "reproach," but it may be influenced by nitwit.