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verb \ˈkrak\

Simple Definition of crack

  • : to break (something) so that there are lines in its surface but it is usually not separated into pieces

  • : to hit or press (something) so hard that it breaks apart or opens suddenly

  • : to hit (someone or something) hard and usually suddenly

Source: Merriam-Webster's Learner's Dictionary

Full Definition of crack

  1. intransitive verb
  2. 1 :  to make a very sharp explosive sound <the whip cracks through the air>

  3. 2 :  to break, split, or snap apart

  4. 3 :  fail: as a :  to lose control or effectiveness under pressure —often used with up b :  to fail in tone <his voice cracked>

  5. 4 :  to go or travel at good speed —usually used with on <the steamboat cracked on>

  6. transitive verb
  7. 1 a :  to break so that fissures appear on the surface <crack a mirror> b :  to break with a sudden sharp sound <crack nuts>

  8. 2 :  to tell especially suddenly or strikingly <crack a joke>

  9. 3 :  to strike with a sharp noise :  rap <then cracks him over the head> <cracked a two-run homer in the fifth — New York Times>

  10. 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 <crack a code> c :  to break into <crack a safe> d :  to open slightly <crack the throttle> e :  to break through (as a barrier) so as to gain acceptance or recognition f :  to show or begin showing (a smile) especially reluctantly or uncharacteristically

  11. 5 a :  to impair seriously or irreparably :  wreck <crack an opponent's courage> b :  to destroy the tone of (a voice) c :  disorder, craze d :  to interrupt sharply or abruptly <the criticism cracked our complacency>

  12. 6 :  to cause to make a sharp noise <cracks his knuckles>

  13. 7 a (1) :  to subject (hydrocarbons) to cracking (2) :  to produce by cracking <cracked gasoline> b :  to break up (chemical compounds) into simpler compounds by means of heat

crack the whip

  1. :  to adopt or apply an authoritative, tyrannical, or threatening approach or policy (as in demanding harder work from employees)

crack wise

  1. :  to make a wisecrack

Examples of crack in a sentence

  1. The hailstones were big enough to crack some windows.

  2. He cracked his collarbone in a skiing accident.

  3. The mirror cracked when she dropped it.

  4. Workers cracked the large rock into three pieces so it could be moved.

  5. The bird cracked the seed on a tree branch.

  6. a tool used for cracking nuts

  7. He cracked open the eggs.

  8. Someone cracked him over the head with a beer bottle.

  9. The baby cracked her chin pretty hard when she fell.

  10. He fell and cracked his elbow on the ice.

Origin and Etymology of crack

Middle English crakken, from Old English cracian; akin to Old High German chrahhōn to resound

First Known Use: before 12th century




Simple Definition of crack

  • : a thin line in the surface of something that is broken but not separated into pieces

  • : a very narrow space or opening between two things or two parts of something

  • : a sudden loud, sharp sound

Source: Merriam-Webster's Learner's Dictionary

Full Definition of crack

  1. 1 a :  a loud roll or peal <a crack of thunder> b :  a sudden sharp noise <the crack of rifle fire>

  2. 2 :  a sharp witty remark :  quip

  3. 3 a :  a narrow break :  fissure <a crack in the ice> b :  a narrow opening <leave the door open a crack> <cracks between floorboards> —used figuratively in phrases like fall through the cracks to describe one that has been improperly or inadvertently ignored or left out <a player who fell through the cracks in the college draft> <children slipping through the cracks of available youth services>

  4. 4 a :  a weakness or flaw caused by decay, age, or deficiency :  unsoundness b :  a broken tone of the voice c :  crackpot

  5. 5 :  moment, instant <the crack of dawn>

  6. 6 :  housebreaking, burglary

  7. 7 :  a sharp resounding blow <gave him a crack on the head>

  8. 8 :  an attempt or opportunity to do something <her first crack at writing a novel> <got first crack at the job opening>

  9. 9 :  a potent form of cocaine that is obtained by treating the hydrochloride of cocaine with sodium bicarbonate to create small chips used illicitly for smoking —called also crack cocaine

Examples of crack in a sentence

  1. The crack runs all the way from the top of the wall to the bottom.

  2. an old patio with grass growing up through the cracks

  3. The vase has a few fine cracks, but it is still usable.

  4. I could see them through the crack in the doorway.

  5. Light came through the cracks in the walls of the barn.

14th Century

First Known Use of crack

14th century




Simple Definition of crack

  • : very good : of excellent quality or ability

Source: Merriam-Webster's Learner's Dictionary

Full Definition of crack

  1. :  of superior excellence or ability <a crack marksman>

CRACK Defined for Kids



verb \ˈkrak\

Definition of crack for Students



  1. 1 :  to break or cause to break with a sudden sharp sound <crack an egg>

  2. 2 :  to break often without completely separating into parts <The ice cracked in several places.>

  3. 3 :  to make or cause to make a sound as if breaking <crack a whip>

  4. 4 :  to open a small amount <crack a window>

  5. 5 :  to tell (a joke) especially in a clever way

  6. 6 :  to lose self-control <He cracked under the strain.>

  7. 7 :  to change in tone quality <My voice cracked from emotion.>

  8. 8 :  to strike or receive a sharp blow <… I bounced sideways and cracked my head on the half-open window … — Jack Gantos, Joey Pigza Loses Control>

  9. 9 :  solve <I cracked the code.>

crack up

  1. 1 :  to have a reputation as a result of praise <The show wasn't as good as it was cracked up to be.>

  2. 2 :  to damage or destroy (a vehicle) by crashing

  3. 3 :  to laugh or cause to laugh <Her costume cracked me up.>




Definition of crack for Students

  1. 1 :  a narrow break or opening <a crack in the glass>

  2. 2 :  a sudden sharp noise <a crack of thunder>

  3. 3 :  a sharp clever remark

  4. 4 :  a broken tone of the voice

  5. 5 :  the beginning moment <I awoke at the crack of dawn.>

  6. 6 :  a sharp blow

  7. 7 :  2attempt <It was my first crack at writing.>




Definition of crack for Students

  1. :  of high quality or ability <crack troops>

Medical Dictionary


noun , often attributive \ˈkrak\

Medical Definition of crack

  1. :  a potent form of cocaine that is obtained by treating the hydrochloride of cocaine with sodium bicarbonate to create small chips used illicitly usually for smoking

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