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boundary - definition and synonyms


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noun [countable]     boundary pronunciation in American English
Word Forms
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  1. 1
    something such as a line on a map that marks where one area of land ends and another begins

    a proposal to redraw the city boundary to include more land for housing

    Akbar extended the boundaries of his empire in the north and south.

    boundary with:

    Rhode Island shares boundaries with the states of Massachusetts, Connecticut, and New York.

    boundary between:

    The Una River forms a natural boundary between the two countries.

  2. 2
    [usually plural] the limits of an activity or experience

    a community in which class boundaries are very clearly drawn

    push back/extend the boundaries of something:

    new research that pushes back the boundaries of genetic science

    cut across boundaries:

    The party’s support cuts across religious boundaries (=is not influenced by differences among religions).

    1. a.
      an imaginary point separating two different qualities, ideas, etc.
      boundary between:

      The boundary between fact and fiction in her writing is often blurred.

  3. 3
    the outer edge of the playing area in cricket

Open Dictionary


a rise in the level of a stream or river

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