deadly - definition and synonyms


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  1. 1
    able or likely to kill people

    This is a potentially deadly disease.

    deadly to:

    Too many water changes can prove deadly to these delicate fish.

    a deadly weapon:

    The police charged him with possession of a deadly weapon.

  2. 2
    [only before noun] complete
    deadly silence:

    A deadly silence followed her announcement.

    a deadly secret:

    Don’t say anything to anyone – this is meant to be a deadly secret.

    in deadly earnest (=completely seriously):

    It started as a joke, but soon they were fighting in deadly earnest.

  3. 3
    informal very boring

    Some of our lectures were pretty deadly!

  4.   From our crowdsourced Open Dictionary
    something that is deadly is fantastic or as good as it possibly can be

    That teacher is deadly! That was a deadly class.

    Submitted by Marg from Australia on 08/08/2009