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set off - 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
Word Forms
present tense
I/you/we/theyset off
he/she/itsets off
present participlesetting off
past tenseset off
past participleset off
  1. 1
    [intransitive] to start a journey, or to start going in a particular direction

    We set off early the next morning.

  2. 2
    [transitive] to cause something to operate, especially by accident

    Jeff pushed open the front door, which set off the alarm.

  3. 3
    [transitive] to make something explode

    Somebody was setting off fireworks down the street.

  4. 4
    [transitive] to cause a situation or a series of events to happen, especially without intending to

    He fears that the election could set off mass protests.

  5. 5
    [transitive] [usually passive] to make someone or something look more attractive by being clearly different from them

    Her plain blue dress was set off by a feather-trimmed hat.

  6. 6
    [transitive] set someone off to make someone start to laugh, cry, or talk a lot

    Just mentioning her father’s death could set her off again.

See also main entry: set
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