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boundary

[boun-duh-ree, -dree] /ˈbaʊn də ri, -dri/
noun, plural boundaries.
1.
something that indicates bounds or limits; a limiting or bounding line.
2.
Also called frontier. Mathematics. the collection of all points of a given set having the property that every neighborhood of each point contains points in the set and in the complement of the set.
3.
Cricket. a hit in which the ball reaches or crosses the boundary line of the field on one or more bounces, counting four runs for the batsman.
Compare six (def 5).
Origin
1620-1630
1620-30; bound3 + -ary
Related forms
transboundary, adjective
Can be confused
boundary, limit, parameter, variable (see synonym study at the current entry; see usage note at parameter)
Synonyms
1. Boundary, border, frontier share the sense of that which divides one entity or political unit from another. Boundary, in reference to a country, city, state, territory, or the like, most often designates a line on a map: boundaries are shown in red. Occasionally, it also refers to a physical feature that marks the agreed-upon line separating two political units: The Niagara River forms part of the boundary between the United States and Canada. Border is more often used than boundary in direct reference to a political dividing line; it may also refer to the region (of, for instance, a country) adjoining the actual line of demarcation: crossing the Mexican border; border towns along the Rio Grande. Frontier may refer to a political dividing line: crossed the Spanish frontier on Tuesday. It may also denote or describe the portion of a country adjoining its border with another country (towns in the Polish frontier ) or, especially in North America, the most remote settled or occupied parts of a country: the frontier towns of the Great Plains. Frontier, especially in the plural, also refers to the most advanced or newest activities in an area of knowledge or practice: the frontiers of nuclear medicine.
Dictionary.com Unabridged
Based on the Random House Dictionary, © Random House, Inc. 2014.
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Examples from the web for boundary
  • The underside of the mantle-the boundary between it and the liquid outer core-is probably rugged terrain.
  • Only then can anyone consider that it has reached the outer boundary of our solar system.
  • Divisions and consolidations have been effected, and new boundary lines have been formed in other instances.
  • These boundary conditions allow convergence between moist maritime air and dry continental air.
  • Voyager data, taken from specific regions within the boundary zone, had offered no hint that the ribbon existed.
  • Tiny bubbles may help lifesaving drugs cross a crucial boundary.
  • But a more important horizon, the boundary to their great progressive inquiry, recedes even as their knowledge advances.
  • Good for a boundary planting, big shrub border, screening.
  • It's not only trials of new drugs that are crossing the futility boundary.
  • The second type of boundary is called a divergent boundary.
British Dictionary definitions for boundary

boundary

/ˈbaʊndərɪ; -drɪ/
noun (pl) -ries
1.
something that indicates the farthest limit, as of an area; border
2.
(cricket)
  1. the marked limit of the playing area
  2. a stroke that hits the ball beyond this limit
  3. the four runs scored with such a stroke, or the six runs if the ball crosses the boundary without touching the ground
Collins English Dictionary - Complete & Unabridged 2012 Digital Edition
© William Collins Sons & Co. Ltd. 1979, 1986 © HarperCollins
Publishers 1998, 2000, 2003, 2005, 2006, 2007, 2009, 2012
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Word Origin and History for boundary
n.

1620s, from bound (n.) + -ary.

Online Etymology Dictionary, © 2010 Douglas Harper
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Word Value for boundary

14
16
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