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noun [countable]     main pronunciation in British English
Word Forms
  1. 2

    the mains

    [plural] British the public supply of water, gas, or electricity
    1. a.
      the point where the supply of water, gas, or electricity enters a building or room

      Turn the water off at the mains before you repair the tap.

Open Dictionary


a rise in the level of a stream or river

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