crack

Etymology 1

From Middle English crakken, craken, from Old English cracian (“to resound, crack”), from Proto-West Germanic *krakōn, from Proto-Germanic *krakōną (“to crack, crackle, shriek”), ultimately from Proto-Indo-European *gerh₂- (“to resound, cry hoarsely”). Cognate with Scots crak (“to crack”), West Frisian kreakje (“to crack”), Dutch kraken (“to crunch, creak, squeak”), Low German kraken (“to crack”), German krachen (“to crash, crack, creak”), Lithuanian gìrgžděti (“to creak, squeak”), Old Armenian կարկաչ (karkačʿ), Sanskrit गर्जति (gárjati, “to roar, hum”).

verb

1. (intransitive) To form cracks.
   It's been so dry, the ground is starting to crack.
2. (intransitive) To break apart under force, stress, or pressure.
   When I tried to stand on the chair, it cracked.
3. (intransitive) To become debilitated by psychological pressure.
   Anyone would crack after being hounded like that.
4. (intransitive) To break down or yield, especially under interrogation or torture.
   When we showed him the pictures of the murder scene, he cracked.
5. (intransitive) To make a cracking sound.
   The bat cracked with authority and the ball went for six.
6. (intransitive, of a voice) To change rapidly in register.
   His voice cracked with emotion.
7. (intransitive, of a pubescent boy's voice) To alternate between high and low register in the process of eventually lowering.
   His voice finally cracked when he was fourteen.
8. (intransitive) To make a sharply humorous comment.
   "I would too, with a face like that," she cracked.
9. (transitive) To make a crack or cracks in.
   The ball cracked the window.
10. (transitive) To break open or crush to small pieces by impact or stress.
    You'll need a hammer to crack a black walnut.
11. (transitive) To strike forcefully.
    She cracked him over the head with her handbag.
    Bedding provided for late session became ammunition—meet ended in riot when Labor man cracked leader on jaw. 10 June 1914, “Pillow Fight In Australian Parliament”, in Independence Daily Reporter
12. (transitive) To open slightly.
    Could you please crack the window?
13. (transitive, figurative) To cause to yield under interrogation or other pressure.
    They managed to crack him on the third day.
14. (transitive, figurative) To solve a difficult problem.
    I've finally cracked it, and of course the answer is obvious in hindsight.
    "… The key to battery trains is more the ability to charge quickly. If you can do that, you've cracked it." November 17 2021, Conrad Landin, “Network News: Vivarail goes forth with fast-charging batteries”, in RAIL, number 944, page 13
15. (transitive) To overcome a security system or component.
    It took a minute to crack the lock, three minutes to crack the security system, and about twenty minutes to crack the safe.
    They finally cracked the code.
16. (transitive) To cause to make a sharp sound.
    to crack a whip
    Hershell cracked his knuckles, a nervous habit that drove Inez crazy[…] 2001, Doug McGuinn, The Apple Indians
17. (transitive) To tell (a joke).
    The performance was fine until he cracked that dead baby joke.
18. (transitive, chemistry) To break down (a complex molecule), especially with the application of heat: to pyrolyse.
    Acetone is cracked to ketene and methane at 700°C.
19. (transitive, computing) To circumvent software restrictions such as regional coding or time limits.
    That software licence will expire tomorrow unless we can crack it.
    Nobody really knows how much actual damage cracking does to the software companies. But as the industry rolls apprehensively toward the uncertain future of an ever-more frictionless electronic marketplace, almost everyone thinks piracy will increase. 1997-04-01, David McCandless, “Warez Wars”, in Wired, →ISSN
20. (transitive, informal) To open a canned beverage, or any packaged drink or food.
    I'd love to crack open a beer.
    Let's crack a tube and watch the game.
    Old Bouvet was waiting in the passage when I entered, and he asked me whether we might not crack a bottle of wine together. 1894, The Strand, volume 8, page 569
21. (obsolete) To brag; to boast.
22. (archaic, colloquial) To be ruined or impaired; to fail.
23. (colloquial) To barely reach or attain (a measurement or extent).
    An underground band that never cracked the Hot 100
    IQ (Intelligence Quotient), number said to measure an individual's intelligence that many experts who clearly didn't crack 125 say overlooks important attributes such as creativity and social skills. 2012, The Onion Book of Known Knowledge, page 102

noun

1. A thin and usually jagged space opened in a previously solid material.
   A large crack had formed in the roadway.
2. A narrow opening.
   We managed to squeeze through a crack in the rock wall.
   Open the door a crack.
   Dimitar Berbatov found the first cracks in the home side's resilience when he pulled one back from close range and Hernandez himself drew the visitors level with a composed finish three minutes later as Bloomfield Road's earlier jubilation turned to despair. January 25, 2011, Phil McNulty, “Blackpool 2 - 3 Man Utd”, in BBC
3. A sharply humorous comment; a wisecrack.
   I didn't appreciate that crack about my hairstyle.
4. (slang) Crack cocaine, a potent, relatively cheap, addictive variety of cocaine; often a rock, usually smoked through a crack-pipe.
   crack head
   And even as a crack fiend, Mama / You always was a black queen, Mama 1995, “Dear Mama”, in Me Against the World, performed by 2Pac
   1. (figurative, humorous) Something good-tasting or habit-forming.
      kitty crack ― catnip
      When did naming foods after a powerful narcotic become a thing?[…]Now the mean streets of New York are rife with “salted crack caramel” ice cream, “pistachio crack” brittle, “crack steak” sandwiches, and “tuna on crack.”] [March 23, 2012, Rob Patronite, Robin Raisfeld, “Your Brain on Food”, in New York Magazine
5. (onomatopoeia) The sharp sound made when solid material breaks.
   The crack of the falling branch could be heard for miles.
6. (onomatopoeia) Any sharp sound.
   The crack of the bat hitting the ball.
   She broke to love in the opening game, only for Bartoli to hit straight back in game two, which was interrupted by a huge crack of thunder that made Lisicki jump and prompted nervous laughter from the 15,000 spectators. June 28, 2011, Piers Newbery, “Wimbledon 2011: Sabine Lisicki beats Marion Bartoli”, in BBC Sport
7. A sharp, resounding blow.
8. (informal) An attempt at something.
   I'd like to take a crack at that game.
9. (vulgar, slang) The vagina.
10. (informal) The space between the buttocks.
    Pull up your pants! Your crack is showing.
11. (Northern England, Scotland, Ireland) Conviviality; fun; good conversation, chat, gossip, or humorous storytelling; good company.
    The party was great crack.
    Being a native of Northumberland, she was enjoying their banter and Geordie good humour. This was what she needed — good company and good crack. 2001, William F. Gray, The Villain, iUniverse, page 214
    "his a bit o' good crack — interesting to talk to" 2004, Bill Griffiths, Dictionary of North East Dialect, Northumbria University Press (quoting Dunn, 1950)
    By the time we've got a good drunk on us there'll be more crack in this valley than the night I pissed on the electric fence! 2006, Patrick McCabe, Winterwood, Bloomsbury, published 2007, page 10
12. (Northern England, Scotland, Ireland) Business; events; news.
    What's the crack?
    What's this crack about a possible merger?
13. (computing) A program or procedure designed to circumvent restrictions or usage limits on software.
    Has anyone got a crack for DocumentWriter 3.0?
14. (hydrodynamics, US, dated) An expanding circle of white water surrounding the site of a large explosion at shallow depth, marking the progress of the shock wave through the air above the water.
    Coordinate term: slick
15. (Cumbria, elsewhere throughout the North of the UK) a meaningful chat.
16. (Internet slang) Extremely silly, absurd or off-the-wall ideas or prose.
17. The tone of voice when changed at puberty.
18. (archaic) A mental flaw; a touch of craziness; partial insanity.
    He has a crack.
19. (archaic) A crazy or crack-brained person.
20. (obsolete) A boast; boasting.
21. (obsolete) Breach of chastity.
22. (obsolete) A boy, generally a pert, lively boy.
23. (slang, dated, UK) A brief time; an instant; a jiffy.
    I'll be with you in a crack.

Etymology 2

Of unknown origin.

adj

1. Highly trained and competent.
   Even a crack team of investigators would have trouble solving this case.
2. Excellent, first-rate, superior, top-notch.
   She's a crack shot with that rifle.
   Fortunately, it is unusual for the crack transatlantic liners to sail or dock on a Saturday, but it is the custom for most holiday cruises to start on that day, returning on Fridays a fortnight or three weeks later. 1962 April, J. N. Faulkner, “Summer Saturday at Waterloo”, in Modern Railways, page 264

noun

1. (obsolete) One who excels; the best.
   1st Gent. What dost think, Jockey? / 2nd Gent. The crack o' the field's against you. 1888 [1637], James Shirley, Hyde Park, act IV, scene iii, page 236