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crack up - definition and synonyms


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90% of the time, speakers of English use just 7,500 words in speech and writing. These words appear in red, and are graded with stars. One-star words are frequent, two-star words are more frequent, and three-star words are the most frequent.



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phrasal verb informal
Word Forms
present tense
I/you/we/theycrack up
he/she/itcracks up
present participlecracking up
past tensecracked up
past participlecracked up

Related words

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  1. 1
    [intransitive] to become mentally ill

    He just cracked up from the stress.

  2. 2
    [intransitive] to suddenly laugh a lot at something

    The girls all cracked up when they saw him.

    1. a.
      [transitive] to make someone laugh a lot

      Little kids just crack me up with the things they say.

  3. 3
    something is not all it’s cracked up to be used for saying that something is not as good as people say that it is
See also main entry: crack

Open Dictionary


the practice of giving birth in the presence of several friends and relatives

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