to break or burst, with or without entire separation of the parts; as, to crack glass; to crack nuts.-to rend with grief or pain; to affect deeply with sorrow; hence, to disorder; to distract; to craze.-to cause to sound suddenly and sharply; to snap; as, to crack a whip.-to utter smartly and sententiously; as, to crack a joke.-to cry up; to extol; -- followed by up.-to burst or open in chinks; to break, with or without quite separating into parts.-to be ruined or impaired; to fail.-to utter a loud or sharp, sudden sound.-to utter vain, pompous words; to brag; to boast; -- with of.-a partial separation of parts, with or without a perceptible opening; a chink or fissure; a narrow breach; a crevice; as, a crack in timber, or in a wall, or in glass.-rupture; flaw; breach, in a moral sense.-a sharp, sudden sound or report; the sound of anything suddenly burst or broken; as, the crack of a falling house; the crack of thunder; the crack of a whip.-the tone of voice when changed at puberty.-mental flaw; a touch of craziness; partial insanity; as, he has a crack.-a crazy or crack-brained person.-a boast; boasting.-breach of chastity.-a boy, generally a pert, lively boy.-a brief time; an instant; as, to be with one in a crack.-free conversation; friendly chat.-of superior excellence; having qualities to be boasted of.