1. (v. t.) To break or burst, with or without entire separation of the parts; as, to crack glass; to crack nuts.

2. (v. t.) To rend with grief or pain; to affect deeply with sorrow; hence, to disorder; to distract; to craze.

3. (v. t.) To cause to sound suddenly and sharply; to snap; as, to crack a whip.

4. (v. t.) To utter smartly and sententiously; as, to crack a joke.

5. (v. t.) To cry up; to extol; -- followed by up.

6. (v. i.) To burst or open in chinks; to break, with or without quite separating into parts.

7. (v. i.) To be ruined or impaired; to fail.

8. (v. i.) To utter a loud or sharp, sudden sound.

9. (v. i.) To utter vain, pompous words; to brag; to boast; -- with of.

10. (n.) 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.

11. (n.) Rupture; flaw; breach, in a moral sense.

12. (n.) 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.

13. (n.) The tone of voice when changed at puberty.

14. (n.) Mental flaw; a touch of craziness; partial insanity; as, he has a crack.

15. (n.) A crazy or crack-brained person.

16. (n.) A boast; boasting.

17. (n.) Breach of chastity.

18. (n.) A boy, generally a pert, lively boy.

19. (n.) A brief time; an instant; as, to be with one in a crack.

20. (n.) Free conversation; friendly chat.

21. (a.) of superior excellence; having qualities to be boasted of.