crack up

British  

verb

1. (intr) to break into pieces

2. informal (intr) to undergo a physical or mental breakdown

3. informal (tr) to present or report, esp in glowing terms

   it's not all it's cracked up to be

4. informal to laugh or cause to laugh uproariously or uncontrollably

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noun

1. informal a physical or mental breakdown

crack up Idioms  

1. Suffer an emotional breakdown, become insane, as in He might crack up under the strain . This usage alludes to the result of cracking one's skull; from the early 1600s to crack alone was used in this way. [ Slang ; early 1900s]

2. Damage or wreck a vehicle or vessel. For example, I'm always afraid that I'll crack up the car .

3. Experience a crash, as in We cracked up on the freeway in the middle of the ice storm .

4. Also, crack someone up . Burst or cause to burst out laughing, as in The audience cracked up , or That joke really cracked me up . [ Slang ; c. 1940] Also see break up , def. 6. All of these expressions derive from crack in the sense of “break into pieces” or “collapse,” a usage dating from the late 1600s. Also see cracked up .

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Example Sentences

It's not clear what made him crack up, but we bet Paul Giamatti had something to do with it.

From BBC • Feb. 13, 2024

She is also the person who, her castmates said, makes David crack up most regularly.

From New York Times • Feb. 1, 2024

Slowly, Gourley introduced his cockamamie mind and razor-sharp wit, learning how to joust with O’Brien and feeling freer to crack up the parade of famous guests.

From Los Angeles Times • Nov. 27, 2023

Developers first drill a well and inject high-pressured water to crack up underground rock.

From Scientific American • Feb. 14, 2023

For the first time in a while, we completely crack up.

From "Five Feet Apart" by Rachael Lippincott

Related Words

• freak out
• go crazy