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English definition of “boundary”

boundary

noun [C]     /ˈbaʊn.dər.i/ /-dri/ US  /-dɚ-/
C1 a real or imagined line that marks the edge or limit of something: The Ural mountains mark the boundary between Europe and Asia. Residents are opposed to the prison being built within the city boundary.Territorial boundaries C1 the limit of a subject or principle: Electronic publishing is blurring the boundaries between dictionaries and encyclopedias.Range and limits
(Definition of boundary noun from the Cambridge Advanced Learner's Dictionary & Thesaurus © Cambridge University Press)
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