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extension - definition and synonyms

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noun     extension pronunciation in American English
Word Forms
  1. 1
    [countable] extra time that you are given to finish a piece of work, especially at college
    extension on:

    I’m going to ask for an extension on this paper.

    1. a.
      extra time that you are given to pay money that you owe
      extension on:

      Will the bank give you an extension on the loan?

    2. b.
      extra time that you are given to use a particular legal document or right

      a visa extension

      extension to:

      Brady wants a two-year extension to his contract.

  2. 2
    [countable] a telephone line that is one of several lines coming from a main line

    What’s your extension?

    I’m at extension 334.

    a new extension number

  3. 3
    [countable] an extra room or rooms added to a building

    The company is building an extension onto the side of the factory.

    extension to:

    He has applied for permission to build a single-story extension to his house.

  4. 4
    [countable] something that you add to a long thin object to make it able to reach somewhere

    This cord isn’t long enough – do you have an extension?

    1. a.


      [plural] long pieces of artificial hair that can be fastened to someone’s hair to make it look longer
  5. 5
    [countable] something that develops from a particular custom, activity, idea, etc.
    extension of:

    Business entertainment seems a natural extension of Japan’s gift-giving culture.

    He sees local history as an extension of family history.

  6. 6
    [uncountable] formal the action of stretching part of your body

    His leg was now capable of full extension.

  7. 7
    [singular/uncountable] an increase in the power of something
    extension of:

    the further extension of state control

  8. 8
    [uncountable] a set of courses provided by a college for people who are not able to go to classes at the college itself or are not able to go during the normal class times
  9. 9
    [countable] computing the last part of the name of a computer file. For example, “exe” and “doc” are extensions.
  10. From our crowdsourced Open Dictionary
    an informal educational process directed toward the rural populationSubmitted by Güneş Aydoğan from Turkey on 08/06/2017
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to manipulate someone psychologically so that they begin to question their own perceptions and memories

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Dunning-Kruger effect

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

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