[crack] vb [ME crakken, fr. OE cracian; akin to OHG chrahhon to resound] vi (bef. 12c) 1: to make a very sharp explosive sound "the whip ~s through the air"
2: to break, split, or snap apart
3: fail: as a: to lose control or effectiveness under pressure--often used with up b: to fail in tone "his voice ~ed"
4: to go or travel at good speed--usu. used with on "the steamboat ~ed on" ~ vt 1 a: to break so that fissures appear on the surface "~ a mirror" b: to break with a sudden sharp sound "~ nuts"
2: to tell esp. suddenly or strikingly "~ a joke"
3: to strike with a sharp noise: rap "then ~s him over the head" "~ed a two-run homer in the fifth --N.Y. Times"
4. a (1): to open (as a bottle) for drinking (2): to open (a book) for studying b: to puzzle out and expose, solve, or reveal the mystery of "~ a code" c: to break into "~ a safe" d: to open slightly "~ the throttle" e: to break through (as a barrier) so as to gain acceptance or recognition
5. a: to impair seriously or irreparably: wreck "~ a car up" b: to destroy the tone of (a voice) c: disorder, craze d: to interrupt sharply or abruptly "the criticism ~ed our complacency"
6: to cause to make a sharp noise "~s his knuckles"
7. a (1): to subject (hydrocarbons) to cracking (2): to produce by cracking "~ed gasoline" b: to break up (chemical compounds) into simpler compounds by means of heat
[2]crack n (14c) 1 a: a loud roll or peal "a ~ of thunder" b: a sudden sharp noise "the ~ of rifle fire"
2: a sharp witty remark: quip 3 a: a narrow break: fissure "a ~ in the ice" b: a narrow opening "leave the door open a ~"
4. a: a weakness or flaw caused by decay, age, or deficiency: unsoundness b: a broken tone of the voice c: crackpot
5: moment, instant "the ~ of dawn"
6: housebreaking, burglary 7: a sharp resounding blow "gave him a ~ on the head" 8: attempt, try "her first ~ at writing a novel" 9: highly purified cocaine in small chips used illicitly usu. for smoking [3]crack adj (1793): of superior excellence or ability "a ~ marksman"