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boundary - definition and synonyms


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noun [countable] boundary pronunciation in American English /ˈbaʊnd(ə)ri/
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.


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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