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set off - definition and synonyms


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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
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  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


a course of study which is much shorter than a university course and focuses on the skills you need for a job, especially computer-related skills

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a stupid person

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an ancient Roman system of underfloor heating, used to heat houses with hot air; from the Latin 'hypocaustum'

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