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effect - definition and synonyms

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noun     effect pronunciation in American English
Word Forms
  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
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a lifestyle focussing on simple pleasures such as comfort and cosiness in the home, and spending time with friends and family

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a form of location that involves the underwater detonation of a bomb which causes sound waves that are picked up by ships

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