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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.
  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



a course of study which is much shorter than a university course and focuses on the skills you need for a job, especially computer-related skills

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an ancient Roman system of underfloor heating, used to heat houses with hot air; from the Latin 'hypocaustum'

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