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effect - definition and synonyms

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noun     effect pronunciation in British English
Word Forms
  1. 1
    [countable/uncountable] a change that is produced in one person or thing by another
    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.

    an adverse/beneficial effect (=a bad/good effect):

    East German companies were suffering the adverse effects of German economic union.

    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 colours 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 film

      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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to manipulate someone psychologically so that they begin to question their own perceptions and memories

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Open Dictionary

Dunning-Kruger effect

the phenomenon by which an incompetent person is too incompetent to understand his own incompetence

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