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addition - definition and synonyms


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noun addition pronunciation in British English /əˈdɪʃ(ə)n/
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  1. 1
    [countable] something that you add to something else
    addition to:

    The latest addition to her business empire is a chain of clothes shops.

    This program is a useful addition to their range of business-related software.

    1. a.
      [uncountable] the action of adding something to something else

      The addition of a few drops of lavender oil to your bath water aids relaxation.

  2. 2
    [uncountable] maths the process of adding two or more numbers or amounts together to make a total

    Lesley is teaching the children addition and subtraction.

  3. 3
    [countable] American an extension that is added to a building

sea lion

in an online conversation, repeatedly asking a person questions which suggest that you are interested in what they are talking about, but are actually intended to annoy them

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