Boundary (&unr_;), n.; pl. Boundaries (&unr_;) [From Bound a limit; cf. LL. bonnarium piece of land with fixed limits.] That which indicates or fixes a limit or extent, or marks a bound, as of a territory; a bounding or separating line; a real or imaginary limit.
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But still his native country lies
Beyond the boundaries of the skies. N. Cotton.
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That bright and tranquil stream, the boundary of Louth and Meath. Macaulay.
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Sensation and reflection are the boundaries of our thoughts. Locke.
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Syn. -- Limit; bound; border; term; termination; barrier; verge; confines; precinct. Bound, Boundary. Boundary, in its original and strictest sense, is a visible object or mark indicating a limit. Bound is the limit itself. But in ordinary usage the two words are made interchangeable.
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