The Collaborative International Dictionary of English v.0.48:

Crack \Crack\, v. i.
   1. To burst or open in chinks; to break, with or without
      quite separating into parts.
      [1913 Webster]

            By misfortune it cracked in the coling. --Boyle.
      [1913 Webster]

            The mirror cracked from side to side. --Tennyson.
      [1913 Webster]

   2. To be ruined or impaired; to fail. [Collog.]
      [1913 Webster]

            The credit . . . of exchequers cracks, when little
            comes in and much goes out.           --Dryden.
      [1913 Webster]

   3. To utter a loud or sharp, sudden sound.
      [1913 Webster]

            As thunder when the clouds in autumn crack. --Shak.
      [1913 Webster]

   4. To utter vain, pompous words; to brag; to boast; -- with
      of. [Archaic.]
      [1913 Webster]

            Ethoipes of their sweet complexion crack. --Shak.
      [1913 Webster]

The Collaborative International Dictionary of English v.0.48:

Crack \Crack\ (kr[a^]k), v. t. [imp. & p. p. Cracked
   (kr[a^]kt); p. pr. & vb. n. Cracking.] [OE. cracken,
   craken, to crack, break, boast, AS. cracian, cearcian, to
   crack; akin to D. kraken, G. krachen; cf. Skr. garj to
   rattle, or perh. of imitative origin. Cf. Crake,
   Cracknel, Creak.]
   [1913 Webster]
   1. To break or burst, with or without entire separation of
      the parts; as, to crack glass; to crack nuts.
      [1913 Webster]

   2. To rend with grief or pain; to affect deeply with sorrow;
      hence, to disorder; to distract; to craze.
      [1913 Webster]

            O, madam, my old heart is cracked.    --Shak.
      [1913 Webster]

            He thought none poets till their brains were
            cracked.                              --Roscommon.
      [1913 Webster]

   3. To cause to sound suddenly and sharply; to snap; as, to
      crack a whip.
      [1913 Webster]

   4. To utter smartly and sententiously; as, to crack a joke.
      --B. Jonson.
      [1913 Webster]

   5. To cry up; to extol; -- followed by up. [Low]
      [1913 Webster]

   To crack a bottle, to open the bottle and drink its
      contents.

   To crack a crib, to commit burglary. [Slang]

   To crack on, to put on; as, to crack on more sail, or more
      steam. [Colloq.]
      [1913 Webster]

The Collaborative International Dictionary of English v.0.48:

Crack \Crack\, n.
   1. 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.
      [1913 Webster]

   2. Rupture; flaw; breach, in a moral sense.
      [1913 Webster]

            My love to thee is sound, sans crack or flaw.
                                                  --Shak.
      [1913 Webster]

   3. 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.
      [1913 Webster]

            Will the stretch out to the crack of doom? --Shak.
      [1913 Webster]

   4. The tone of voice when changed at puberty.
      [1913 Webster]

            Though now our voices
            Have got the mannish crack.           --Shak.
      [1913 Webster]

   5. Mental flaw; a touch of craziness; partial insanity; as,
      he has a crack.
      [1913 Webster]

   6. A crazy or crack-brained person. [Obs.]
      [1913 Webster]

            I . . . can not get the Parliament to listen to me,
            who look upon me as a crack and a projector.
                                                  --Addison.
      [1913 Webster]

   7. A boast; boasting. [Obs.] "Crack and brags." --Burton.
      "Vainglorius cracks." --Spenser.
      [1913 Webster]

   8. Breach of chastity. [Obs.] --Shak.
      [1913 Webster]

   9. A boy, generally a pert, lively boy. [Obs.]
      [1913 Webster]

            Val. 'T is a noble child. Vir. A crack, madam.
                                                  --Shak.
      [1913 Webster]

   10. A brief time; an instant; as, to be with one in a crack.
       [Eng. & Scot. Colloq.]
       [1913 Webster]

   11. Free conversation; friendly chat. [Scot.]
       [1913 Webster]

             What is crack in English? . . . A crack is . . . a
             chat with a good, kindly human heart in it. --P. P.
                                                  Alexander.
       [1913 Webster]

   12. a witty remark; a wisecrack.
       [PJC]

   13. a chance or opportunity to do something; an attempt; as,
       I'll take a crack at it.
       [PJC]

   14. a form of cocaine, highly purified and prepared as small
       pellets, especially suitable for smoking; -- also called
       rock. Used in this form it appears to be more addicting
       than cocaine powder. [slang]
       [PJC]

The Collaborative International Dictionary of English v.0.48:

Crack \Crack\, a.
   Of superior excellence; having qualities to be boasted of;
   as, a crack shot. [Colloq.]
   [1913 Webster]

         One of our crack speakers in the Commons. --Dickens.
   [1913 Webster]

The Collaborative International Dictionary of English v.0.48:

Cocaine \Co"ca*ine\, n. (Chem.)
   A powerful narcotic alkaloid, C17H21NO4, obtained from the
   leaves of coca. It is a bitter, white, crystalline substance,
   and is remarkable for producing local insensibility to pain.
   It is classified as addictive and is not available in the U.
   S. without a prescription, but is nevertheless one of the
   most widespread illegal drugs of abuse. It is used in several
   forms, including small pellets of free base, called crack.
   Most of the cacaine illegally used in the U.S. is imported.
   [1913 Webster +PJC]

WordNet (r) 3.0 (2006):

crack
    adj 1: of the highest quality; "an ace reporter"; "a crack
           shot"; "a first-rate golfer"; "a super party"; "played
           top-notch tennis"; "an athlete in tiptop condition"; "she
           is absolutely tops" [syn: ace, A-one, crack,
           first-rate, super, tiptop, topnotch, top-notch,
           tops(p)]
    n 1: a long narrow opening [syn: crack, cleft, crevice,
         fissure, scissure]
    2: a narrow opening; "he opened the window a crack" [syn: gap,
       crack]
    3: a long narrow depression in a surface [syn: crevice,
       cranny, crack, fissure, chap]
    4: a sudden sharp noise; "the crack of a whip"; "he heard the
       cracking of the ice"; "he can hear the snap of a twig" [syn:
       crack, cracking, snap]
    5: a chance to do something; "he wanted a shot at the champion"
       [syn: shot, crack]
    6: witty remark [syn: wisecrack, crack, sally, quip]
    7: a blemish resulting from a break without complete separation
       of the parts; "there was a crack in the mirror"
    8: a purified and potent form of cocaine that is smoked rather
       than snorted; highly addictive [syn: crack, crack
       cocaine, tornado]
    9: a usually brief attempt; "he took a crack at it"; "I gave it
       a whirl" [syn: crack, fling, go, pass, whirl,
       offer]
    10: the act of cracking something [syn: fracture, crack,
        cracking]
    v 1: become fractured; break or crack on the surface only; "The
         glass cracked when it was heated" [syn: crack, check,
         break]
    2: make a very sharp explosive sound; "His gun cracked"
    3: make a sharp sound; "his fingers snapped" [syn: snap,
       crack]
    4: hit forcefully; deal a hard blow, making a cracking noise;
       "The teacher cracked him across the face with a ruler"
    5: pass through (a barrier); "Registrations cracked through the
       30,000 mark in the county" [syn: break through, crack]
    6: break partially but keep its integrity; "The glass cracked"
    7: break suddenly and abruptly, as under tension; "The pipe
       snapped" [syn: snap, crack]
    8: gain unauthorized access computers with malicious intentions;
       "she cracked my password"; "crack a safe"
    9: suffer a nervous breakdown [syn: crack up, crack, crock
       up, break up, collapse]
    10: tell spontaneously; "crack a joke"
    11: cause to become cracked; "heat and light cracked the back of
        the leather chair"
    12: reduce (petroleum) to a simpler compound by cracking
    13: break into simpler molecules by means of heat; "The
        petroleum cracked"

Moby Thesaurus II by Grady Ward, 1.0:

758 Moby Thesaurus words for "crack":
   Daedalian, Parthian shot, above par, abrade, abrasion, abysm,
   abyss, account for, ace, address, adept, adroit, allegation,
   allegorize, alligator, answer, aperture, aphorism, apostrophe,
   apothegm, approach, apt, arroyo, artistic, assay, assertion,
   attempt, authoritative, averment, back answer, band, bang, bar,
   bark, bash, bastinado, bat, beating, belt, bezel, bid, biff,
   birthmark, bit, blackhead, blast, blaze, bleb, blemish, blister,
   bloody, blow, bon mot, bonk, boom, bottom, boutade, bowshot,
   box canyon, brand, bravura, breach, break, break open, break up,
   breakage, breath, breathing, brief span, bright idea,
   bright thought, brilliant, brilliant idea, broach, broaching, bug,
   bulla, bump, burn, burn in, burn off, burst, bust, canal, canalize,
   canyon, carve, cast, catch, caustic remark, cauterize, cavity,
   chafe, chamfer, channel, chap, char, chase, chasm, check, chimney,
   chink, chip, chisel, chop, cicatrix, cicatrize, clack, clap,
   clarify, clash, claw, clean, clear up, clearing, cleave, cleft,
   cleuch, clever, click, clip, clobber, close quarters, close range,
   clough, clout, clump, coal, col, coldcock, come apart,
   come unstuck, comeback, comedo, comment, conceit, concussion,
   coordinated, corrugate, corrugation, coulee, couloir, coup, crack,
   crack up, crackerjack, cracking, crackle, crackling, cranny, crash,
   crater, craze, crepitate, crepitation, crevasse, crevice, crimp,
   crump, cryptanalyze, cunning, cupel, cut, cut apart, cut open,
   cute, cutting remark, cwm, dado, daedal, dash, deal, deal a blow,
   debug, decipher, deck, declaration, decode, decrepitate,
   decrepitation, decrypt, deface, defacement, defect, defection,
   deficiency, defile, deform, deformation, deformity, deft, dell,
   demonstrate, demythologize, detonate, detonation, dexterous,
   dextrous, dictum, dig, dike, dint, diplomatic, discharge,
   disclosure, discontinuity, disentangle, disfiguration, disfigure,
   disfigurement, disintegrate, dispart, distort, distortion, ditch,
   divaricate, divide, divine, do, donga, dope, dope out, draw,
   drawback, drollery, drub, drubbing, drumming, dump, earreach,
   earshot, effort, elucidate, endeavor, engrave, engraving,
   enlighten, epigram, essay, euhemerize, excavation, excellent,
   exclamation, exemplify, exfoliate, experiment, expert, explain,
   explain away, explicate, explode, explosion, exposit, expound,
   expression, facetiae, failing, failure, fall to pieces, fancy,
   fathom, fault, faute, fenestra, fetch, fetch a blow, figure out,
   find out, find the answer, fissure, fistula, flame, flap, flash,
   flash burn, flash of wit, flaw, fleer, flight of wit, fling, flip,
   flop, flout, flume, flute, fluting, fly open, foible, fontanel,
   foolery, foramen, found, fracture, frailty, fray, frazzle, freckle,
   fret, fulminate, fulmination, furrow, fusillade, gag, gall, gambit,
   gap, gape, gash, gat, get, get right, gibe, gibing retort,
   give away, give reason for, give the meaning, give way, go,
   go haywire, go into hysterics, go off, go to pieces, goffer, good,
   goodish, gorge, gouge, graceful, greeting, groove, guess,
   guess right, gulch, gulf, gully, gunshot, hair, hair space,
   hairbreadth, hairsbreadth, half a jiffy, half a mo, half a second,
   half a shake, handy, happy thought, have it, hemangioma, hiatus,
   hickey, high-class, high-grade, high-quality, high-test, hit,
   hit a clip, hit it, hole, hollow, hurt, illuminate, illustrate,
   imperfection, inadequacy, inch, incise, incision, infirmity,
   ingenious, injure, injury, inlet, instant, interjection, interpret,
   interstice, interval, jab, jape, jeer, jest, jiff, jiffy, joint,
   keloid, kink, kloof, knock, knock cold, knock down, knock out,
   lacerate, laceration, lacuna, lay open, laying open, leak,
   leg-pull, lentigo, lesion, let have it, lick, list, little,
   little problem, little ways, lose courage, lose self-control,
   magisterial, maim, make clear, make mincemeat of, make out,
   make plain, mar, master, masterful, masterly, maul, mention,
   microgroove, microsecond, milium, millisecond, minute, moat, mock,
   mole, moment, mortal wound, mot, move, mutilate, mutilation,
   nasty crack, neat, needle scar, nevus, niche, no mean, notch, note,
   nullah, observation, offer, ope, open, open the lock, open up,
   opening, opening up, orifice, outlet, oxidate, oxidize, parch,
   part, parting shot, pass, passage, passageway, paste, pelt,
   percussion, persiflage, phrase, pierce, pimple, pistol shot, pit,
   play of wit, pleasantry, pleat, plow, plumb, plunk, pock, pockmark,
   poke, politic, pop, popularize, pore, port-wine mark,
   port-wine stain, position, potshot, pound, problem, professional,
   proficient, pronouncement, psych, psych out, punch, puncture,
   pustule, put-down, put-on, puzzle out, pyrolyze, question, quick,
   quip, quips and cranks, quite some, rabbet, rap, rationalize,
   ravel, ravel out, ravine, ready, reflection, remark, rend, rent,
   repartee, report, resolve, resourceful, retort, riddle, rifle,
   rifling, rift, rime, rip, riposte, rive, ruck, rude reproach, run,
   rupture, rut, sally, salvo, savage, say, saying, scab, scald,
   scale, scar, scarify, scintillation, scissure, scoff, scorch,
   score, scotch, scrape, scratch, scuff, scurrility, seam, sear,
   sebaceous cyst, sec, second, second-degree burn, sentence,
   separate, shake, shatter, shed light upon, shiver, short answer,
   short distance, short piece, short way, shortcoming, shot, show,
   show how, show the way, simplify, singe, sizzling, skilled,
   skillful, skin, slam, slap, slash, slat, slice, slick, slit, slog,
   slot, slug, smack, smart crack, smart saying, smash, smite, snag,
   snap, snapping, snappy comeback, soak, sock, solder, solve, some,
   something missing, sore, sort out, space, span, spell out, spit,
   spitting, spitting distance, splat, splinter, split, split second,
   splitting, sprain, spread, spread out, spring a leak, spring open,
   stab, stab wound, stagger, start, statement, statesmanlike, step,
   stick, stoma, strain, strawberry mark, streak, streaking, stria,
   striate, striation, striature, striga, strike, strike at, striola,
   stripe, striping, stroke, stroke of wit, strong bid, sty, stylish,
   subjoinder, sulcation, sulcus, superior, swap, swat, swing,
   swing open, swinge, swipe, tactful, taint, tap, tattoo, taunt,
   tear, tear open, tentative, the compleat, the complete,
   third-degree burn, thought, throw light upon, throw open,
   throwing open, thump, thwack, tick, time, torrefy, track, trauma,
   traumatize, trench, trial, trial and error, trice, trough, try,
   turn of thought, twink, twinkle, twinkling, twist, twit, twitch,
   two shakes, uncorking, undertaking, undo, unfold, unlock, unravel,
   unriddle, unscramble, unstopping, untangle, untwist, unweave,
   utterance, valley, verbal thrust, verruca, vesicate, vesicle,
   virtuoso, void, volley, vulcanize, vulnerable place, wadi, wale,
   wallop, warp, wart, weak link, weak point, weakness, weal, weld,
   well-done, well-worn groove, welt, wen, whack, wham, whap, whirl,
   whitehead, whomp, whop, wink, wisecrack, witticism, word, work,
   work out, workmanlike, wound, wounds immedicable, wrench, wrinkle,
   yak, yawn, yerk



The Jargon File (version 4.4.7, 29 Dec 2003):

crack


    [warez d00dz]

    1. v. To break into a system (compare cracker).

    2. v. Action of removing the copy protection from a commercial program.
    People who write cracks consider themselves challenged by the copy
    protection measures. They will often do it as much to show that they are
    smarter than the developer who designed the copy protection scheme than to
    actually copy the program.

    3. n. A program, instructions or patch used to remove the copy protection
    of a program or to uncripple features from a demo/time limited program.

    4. An exploit.