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oil - definition and synonyms

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noun     oil pronunciation in American English
Word Forms
  1. 1
    [uncountable] a thick dark smooth liquid from under the ground, used for making gas and other fuels

    The Middle Eastern countries produce most of the world’s oil.

    We need to do more to reduce our dependence on foreign oil.

    Heat can be provided by oil, gas, or electricity.

    crude oil (=oil in its natural state):

    A large tanker can carry several million tons of crude oil.

    1. a.
      [only before noun] relating to this liquid

      Oil prices will probably rise again next year.

      an oil company

      China has large coal and oil reserves.

  2. 2
    [countable/uncountable] a thick smooth liquid used in an engine, so it will work smoothly

    Change the oil in your car every 3,000 miles.

  3. 4
    [countable/uncountable] [usually plural] a type of paint that contains oil
    in oils:

    I prefer to work in oils.

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

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

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