Backfire

v. (ring) 1 (of an engine or vehicle) ignite or explode too early in the cylinder or exhaust. 2 (of a plan etc.) rebound adversely on its originator. backformation n. 1 formation of a word from its seeming derivative (e.g. laze from lazy). 2 word so formed. backgammon n. boardgame with pieces moved according to throws of the dice. [from BACK + obsolete form of GAME]