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effect - definition and synonyms


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noun effect pronunciation in American English /ɪˈfekt/
Word Forms
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  1. 1
    [countable/uncountable] a change that is produced in one person or thing by another
    an adverse/beneficial effect (=a bad/good effect): East German companies were suffering the adverse effects of German economic union.
    effect on/upon: Scientists are studying the chemical’s effect on the environment.
    have an effect on something: Any change in lifestyle will have an effect on your health.
    have some/little/no effect: The NAFTA agreement has had little effect on the lives of most Americans.
    reduce/counter the effect(s) of something: Relaxation can reduce the negative effects of stress on the immune system.
  2. 2
    [countable] an appearance or reaction that is deliberately produced, for example by a writer, artist, or musician
    The bold colors in this room create a dramatic effect.
    That’s exactly the effect I wanted.
    get/produce/achieve an effect: Students should learn how they can achieve different stylistic effects in their writing.
    1. a.


      [plural] cinema special artificial images and sounds created for a movie
      I didn’t think much of the plot, but the effects were amazing.
    2. b.
      [countable] [usually singular] an artificial appearance given to a surface or to an object
      marble-effect wallpaper
  3. 3
    [countable] [usually singular] something that regularly happens, according to a law, for example in science
    the Doppler effect
    what economists call “the multiplier effect”
  4. 4



    personal effects

    [plural] formal the things that belong to you



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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