boundary

noun

bound·​ary ˈbau̇n-d(ə-)rē How to pronounce boundary (audio)
plural boundaries
Synonyms of boundary
: something that indicates or fixes a limit or extent
Those two trees mark the boundary of our property.
the mountain range that forms the country's northern boundary
boundaryless
ˈbau̇n-d(ə-)rē-ləs How to pronounce boundary (audio)
adjective
boundarylessness noun

Synonyms of boundary

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Examples of boundary in a Sentence

Those two trees mark the boundary of our property. The river forms the country's western boundary. at the boundary between fact and fiction You need to set boundaries with your children. Did he violate the boundaries of the doctor-patient relationship?
Recent Examples on the Web
Examples are automatically compiled from online sources to show current usage. Read More Opinions expressed in the examples do not represent those of Merriam-Webster or its editors. Send us feedback.
Woodland voters will decide two ballot measures in November that could increase city revenue and expand municipal utility services beyond city boundaries. — Daniel Lempres, Sacbee.com, 19 Oct. 2026 Dieffenbach was on point from the first whistle to the last, unafraid to make difficult throws over the middle of the field and on the boundaries. — Connor Dullinger, Los Angeles Times, 19 Oct. 2026 Caroline Klancke, director of the independent, nonpartisan Florida Ethics Institute in Tallahassee, said there’s no inherent issue with public officials having private employment, but certain boundaries need to be in place. — Michelle Marchante, Miami Herald, 19 Oct. 2026 The arch would be built in the middle of a traffic circle tucked inside Washington's boundaries near Arlington National Cemetery. — Arkansas Online, 18 Oct. 2026 See All Example Sentences for boundary

Word History

Etymology

bound entry 6 + -ary entry 1

First Known Use

1598, in the meaning defined above

Time Traveler
The first known use of boundary was in 1598

Phrases Containing boundary

Browse Nearby Words

bound and gagged
boundary
boundary condition
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Cite this Entry

“Boundary.” Merriam-Webster.com Dictionary, Merriam-Webster, https://www.merriam-webster.com/dictionary/boundary. Accessed 21 Oct. 2026.

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Kids Definition

boundary

noun
bound·​ary ˈbau̇n-d(ə-)rē How to pronounce boundary (audio)
plural boundaries
: something that points out or shows a limit or end : dividing line

Legal Definition

boundary

noun
bound·​ary
plural boundaries
: a theoretical line that marks the limit of an area of land
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