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virus - definition and synonyms


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noun [countable] virus pronunciation in British English /ˈvaɪrəs/
Word Forms
  1. 1
    biology a simple living thing that is smaller than bacteria and that can enter your body and make you ill. If your body can protect itself against a particular virus, then you are immune to it. A vaccine is a medicine that makes you immune to a particular virus

    Malaria is caused by a virus carried by mosquitos.

    the AIDS virus

    1. a.
      a disease caused by a virus

      I’ve been in bed all week with a virus.

    See also bacteria
  2. 2
    computing a program that enters your computer and damages or destroys information that you have stored

    Most viruses are spread over the Internet.



a title used before a man or woman's name as a gender-neutral alternative to Mr, Ms, etc

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another way of saying congratulations, or that something/someone looks nice or fascinating

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