crack down

crack  (krk)

v. cracked, crack·ing, cracks

v.intr.

1. To break or snap apart.

2. To make a sharp snapping sound.

3. To break without complete separation of parts; fissure: The mirror cracked.

4. To change sharply in pitch or timbre, as from hoarseness or emotion. Used of the voice.

5. To break down; fail: The defendant's composure finally began to crack.

6. To have a mental or physical breakdown: cracked under the pressure.

7. To move or go rapidly: was cracking along at 70 miles an hour.

8. Chemistry To break into simpler molecules by means of heat.

v.tr.

1. To cause to make a sharp snapping sound.

2. To cause to break without complete separation of parts: cracked the glass.

3.

a. To break with a sharp snapping sound. See Synonyms at break.

b. To crush (corn or wheat, for example) into small pieces.

4. To open to a slight extent: cracked the window to let in some air.

5. To strike with a sudden sharp sound.

6. Informal

a. To break open or into: crack a safe.

b. To open up for use or consumption: crack a book; cracked a beer.

c. To break through (an obstacle) in order to win acceptance or acknowledgement: finally cracked the "men-only" rule at the club.

7. To discover the solution to, especially after considerable effort: crack a code.

8. To cause (the voice) to crack.

9. Informal To tell (a joke), especially on impulse or in an effective manner.

10. To cause to have a mental or physical breakdown.

11. To impair or destroy: Their rude remarks cracked his equanimity.

12. To reduce (petroleum) to simpler compounds by cracking.

n.

1. A sharp snapping sound, such as the report of a firearm.

2.

a. A partial split or break; a fissure.

b. A slight narrow space: The window was open a crack.

3. A sharp resounding blow.

4.

a. A mental or physical impairment; a defect.

b. A breaking, harshly dissonant vocal tone or sound, as in hoarseness.

5. An attempt or try: gave him a crack at the job; took a crack at photography.

6. A witty or sarcastic remark. See Synonyms at joke.

7. A moment; an instant: at the crack of dawn.

8. Irish Fun; amusement.

9. Slang Crack cocaine.

adj.

Excelling in skill or achievement; first-rate: a crack shot; a crack tennis player.

Phrasal Verbs:

crack down

To act more forcefully to regulate, repress, or restrain: The police cracked down on speeding.

crack up Informal

1. To praise highly: He was simply not the genius he was cracked up to be.

2.

a. To damage or wreck (a vehicle or vessel): crack up a plane; crack up a boat.

b. To wreck a vehicle in an accident: cracked up on the expressway.

3. To have a mental or physical breakdown: crack up from overwork.

4. To experience or cause to experience a great deal of amusement: really cracked up when I heard that joke.

Idiom:

crack the whip

To behave in a domineering manner; demand hard work and efficiency from those under one's control.

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[Middle English craken, from Old English cracian; see ger-² in Indo-European roots.]

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crack down

Verb

crack down on to take severe measures against

Noun

crackdown

severe or repressive measures

Thesaurus

Verb

1.

crack down - repress or suppress (something regarded as undesirable); "The police clamped down on illegal drugs" clamp down confine, limit, throttle, trammel, restrain, restrict, bound - place limits on (extent or access); "restrict the use of this parking lot"; "limit the time you can spend with your friends"