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thorough - definition and synonyms

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adjective     thorough pronunciation in American English
  1. 1
    including everything that is possible or necessary

    The key to a good interview is thorough preparation.

    a thorough investigation/examination/search:

    a thorough and painstaking investigation by the police

    a thorough understanding/knowledge:

    She has a thorough understanding of the business.

    1. a.
      someone who is thorough does everything that they should and leaves nothing out

      The doctor was very thorough and asked lots of questions.

  2. 2
    [only before noun] complete: used for emphasizing how bad someone or something is

    It’s all a thorough nuisance.

    The project was a thorough disaster.

derived word


noun [uncountable]


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

BuzzWord Article

Open Dictionary

Dunning-Kruger effect

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

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