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deadly

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adjective British English pronunciation: deadly /ˈdedli/ 
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adjectivedeadly
comparativedeadlier
superlativedeadliest

Related dictionary definitions

  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.

    Thesaurus entry for this meaning of  deadlyThesaurus entry for this meaning of deadly
  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.

    Thesaurus entry for this meaning of  deadlyThesaurus entry for this meaning of deadly
  3. 3
    informal very boring

    Some of our lectures were pretty deadly!

    Thesaurus entry for this meaning of  deadlyThesaurus entry for this meaning of deadly

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This is the British English definition of deadly. View American English definition of deadly.

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