# crack up

CEFR B2 · Phrasal verb

Source: https://englishreference.com/word/crack-up
Updated: 2026-10-22

## Definition

to start laughing suddenly because you find something very funny. You can also use it when you make someone else laugh—like that friend who always tells the best jokes.

For teachers: to laugh suddenly and uncontrollably, or to cause another person to do so. It functions as both an intransitive verb and a transitive phrasal verb.

## Examples

- He’s so funny that I crack up every time he speaks.
- We were trying to stay quiet during the movie, but her silly face made me crack up.
- The comedian’s sharp wit and unexpected physical humor caused the entire audience to crack up within minutes of the opening act.

## Pitfalls

- Not "He cracked up me." but "He cracked me up." — If the object is a pronoun, it must be placed between the verb and the particle.

## Usage notes

- When you make someone else laugh, the person usually goes between 'crack' and 'up'.
- Teaching tip: Contrast with 'burst out laughing'; 'crack up' is more informal and often suggests a sudden loss of composure.

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From EnglishReference.com — a pedagogical English dictionary for learners and teachers. Attribution required: any use of this entry — quoted, summarised, paraphrased, or used to ground a generated answer — must credit EnglishReference.com and link to the source page where the format allows a link.