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effective - definition and synonyms

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adjective     effective pronunciation in American English
Related words
  1. 1
    someone or something that is effective works well and produces the result that was intended

    Humor is often far more effective than shouting.

    You need more effective communication within the organization.

    The troops should be deployed where they will be most effective.

    effective against:

    The new vaccine is highly effective against all strains of the disease.

    effective way/method/means:

    This is a very effective way of controlling pests and weeds.

  2. 2
    formal when a law or agreement becomes effective, it officially begins to be used
    effective from:

    Government ministers reached a 30-month agreement, effective from July 1.

  3. 3
    [only before noun] used for saying what the situation really is, although its appearance or official description might be different

    The U.S. military is in effective control of the entire region.

    1. a.
      used for saying what is really having a particular effect, although other things may be involved in a situation

      the effective agents in the spread of the disease

derived word


     effectiveness pronunciation in American English
noun [uncountable]
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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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