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noun operation pronunciation in American English /ˌɑpəˈreɪʃ(ə)n/
Word Forms
  1. 1
    [countable] a planned activity involving a lot of people, especially soldiers or police officers

    This was the biggest military operation in 20 years.

    Undercover operations led to the arrest of the gang.

    rescue/relief/cleanup operation:

    The cleanup operation will take weeks.

  2. 2
    [countable] an action or set of actions that is necessary to achieve something

    Connecting the water supply is a very simple operation.

    The computer performs this operation many times every day.

  3. 3
    [countable] the process of cutting into someones body for medical reasons

    a stomach/heart operation

    have/undergo an operation:

    The baby had to have an operation, but he’s fine now.

    operation on:

    She may need an operation on her knee.

    do/perform/carry out an operation:

    A very experienced heart surgeon will perform the operation.

  4. 4
    [uncountable] the way that something such as a system or service operates

    We are visiting schools to explain the operation of the new exam system.

    1. a.
      used about the way that a machine or piece of equipment operates

      Something was interfering with the radar equipment’s operation.

    2. b.
      used about the way that something such as a rule or an idea is used

      Science investigates the operation of general laws.

  5. 5
    [countable] a company, or a part of a large company

    The company has recently expanded its international operation.

    The group is selling its overseas operations.

  6. 6
    [uncountable] the process of controlling something or of making it work

    Operation of this equipment requires special training.



… a teaching method in which groups of children learn independently using a computer linked to the internet

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Open Dictionary


a derogatory word used for referring to people in the banking and investment industry who are thought of as taking serious risks in order to increase their own earnings …

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