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rock - definition and synonyms

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noun     rock pronunciation in American English
Word Forms
  1. 1
    [uncountable] the hard solid substance that forms part of the Earth’s surface

    We had to dig down through a twelve-inch layer of rock.

    1. a.
      [countable] a large piece of stone lying on the ground

      She ran over the fallen rocks toward him.

    2. b.
      [countable] American a small stone
    3. c.
      [countable] a large piece of stone that rises up from the ground or from under the ocean

      a castle built on a big rock

    4. d.


      [plural] a group of rocks along the edge of the land or under the surface of the ocean

      The waves crashed against the rocks.

  2. 2



    rock music

    [uncountable]Sound effect rock music

    a rock star

  3. 3
    [countable] informal a jewel, especially a diamond
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