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necessary - definition and synonyms


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adjective necessary pronunciation in British English /ˈnesəs(ə)ri/
  1. 1
    essential or needed in order to do something, provide something, or make something happen

    I don’t want to be disturbed unless it’s absolutely necessary.

    necessary for:

    basic foods regarded as necessary for health

    necessary for:

    What type of clothing is necessary for survival at these altitudes?

    it is necessary for someone to do something:

    It was necessary for all students to register a week in advance.

    if necessary:

    I can take your place at the meeting tomorrow if necessary.

    as necessary:

    We’ll be adding more workers as necessary (=as they are needed).

  2. 2
    certain to happen or exist

    The necessary risks of medicines must be weighed against their benefits.


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