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mass - definition and synonyms


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noun mass pronunciation in American English /mæs/
Word Forms
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  1. 1
    [countable] a large quantity or number
    mass of:

    We need to turn this mass of evidence into a coherent argument.

    There’s a mass of competing anti-virus programs you can choose from.

    1. a.


      [plural] mainly British informal a lot
      mass of:

      Masses of people attended the meeting.

  2. 2
    [countable] a lump or amount of a substance that does not have a clear or definite shape

    The vegetables had turned into a sticky mass at the bottom of the pan.

    mass of:

    All that was left of the car was a mass of twisted metal.

    a mass of dark cloud

    Synonyms and related words
  3. 3
    [singular] a large crowd of people
    a seething mass (=moving in all directions):

    a seething mass of protesters

    mass of:

    A mass of people followed the procession.

    1. a.

      the masses

      [plural] ordinary people who are not rich or famous. This word usually shows that you think ordinary people are not important or intelligent

      It is entertainment that will appeal to the masses.

  4. 4




    [countable/uncountable] the main religious ceremony of the Roman Catholic church

    They go to mass every Sunday.

    1. a.
      [countable] music a piece of music written for some of the prayers in the mass

      Bach’s Mass in B Minor

      Synonyms and related words
  5. 5
    [uncountable] chemistry the amount of matter that something contains
    See also critical mass

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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an electric skateboard

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