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act - definition and synonyms


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noun act pronunciation in British English /ækt/
Word Forms
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  1. 1
    [countable] a single thing that someone does
    act of violence/vandalism/terrorism/kindness/bravery/desperation etc: No act of kindness is ever wasted.
    We strongly condemn any act of violence against innocent people.
    unlawful/criminal/wrongful/illegal etc act: groups committing criminal acts
  2. 2
    [singular] a way of behaving that does not show what someone is really like or what they really feel
    She isn’t really upset: it’s all an act.
    put on an act: She’s just putting on an act because the boys are here.
  3. 3
    [countable] a short performance by a comedian, magician, or other performer
    He eats fire as part of his act.
    1. a.
      a singer, band, or other person or group who performs on stage. Two people who perform together, especially two comedians, are called a double act
      They remain one of rock music’s most exciting live acts.
  4. 4
    [countable] one of the parts that a play, opera, or ballet is divided into. Each act is divided into two or more scenes
    The scene occurs at the beginning of the first act.
    Act 1 Scene 2
  5. 5
    [countable] a law passed by a countrys government
    the Data Protection Act
    an act of Parliament



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

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