bound·​ary | \ ˈbau̇n-d(ə-)rē How to pronounce boundary (audio) \
plural boundaries

Definition 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

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Other Words from boundary

boundaryless \ ˈbau̇n-​d(ə-​)rē-​ləs How to pronounce boundary (audio) \ adjective
boundarylessness noun

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?
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Recent Examples on the Web This time around the Dolphins altered their approach against Waller, having cornerback Byron Jones, who was a college safety, on Waller and having Nik Needham work on the boundary. Steve Svekis,, 27 Sep. 2021 The remains were found on the east boundary of Grand Teton National Park in Wyoming. Greg Hanlon,, 20 Sep. 2021 The remains were found in the area of the Spread Creek Dispersed Camping Area, located in the Bridger-Teton National Forest on the east boundary of Grand Teton National Park, Mr. Jones said, adding that the campsite will remain closed. New York Times, 19 Sep. 2021 On Thursday, the board agreed on most boundaries across the state but couldn’t agree on the boundary between the Matanuska-Susitna Borough and the Municipality of Anchorage. James Brooks, Anchorage Daily News, 10 Sep. 2021 Found on the boundary between the Qatari land and sea, the mangrove thickets provide a valuable nursery habitat for many types of coastal and offshore fish and crustaceans and a sanctuary for flamingos, herons and other seasonal bird life. Dimitris Sideridis, CNN, 27 Aug. 2021 On the southern boundary, near 12th Street South, a rain garden will appear as a wetland meadow. Washington Post, 7 July 2021 Rather than focus on a boundary between the chaotic region and the region of regular motion, Kol has proposed a theoretical hole in the chaotic system. Caroline Delbert, Popular Mechanics, 13 May 2021 Moehrig would fit as a single-high safety and center fielder but can also play the slot and out on the boundary at cornerback. Brett Knight, Forbes, 21 Apr. 2021

These example sentences are selected automatically from various online news sources to reflect current usage of the word 'boundary.' Views expressed in the examples do not represent the opinion of Merriam-Webster or its editors. Send us feedback.

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First Known Use of boundary

1598, in the meaning defined above

History and Etymology for boundary

bound entry 6 + -ary entry 1

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Time Traveler for boundary

Time Traveler

The first known use of boundary was in 1598

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Dictionary Entries Near boundary

bound and gagged


boundary condition

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Statistics for boundary

Last Updated

9 Oct 2021

Cite this Entry

“Boundary.” Dictionary, Merriam-Webster, Accessed 15 Oct. 2021.

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More Definitions for boundary



English Language Learners Definition of boundary

: something (such as a river, a fence, or an imaginary line) that shows where an area ends and another area begins
: a point or limit that indicates where two things become different
: unofficial rules about what should not be done : limits that define acceptable behavior


bound·​ary | \ ˈbau̇n-də-rē How to pronounce boundary (audio) , ˈbau̇n-drē \
plural boundaries

Kids Definition of boundary

: something that points out or shows a limit or end : a dividing line


plural boundaries

Legal Definition of boundary

: a theoretical line that marks the limit of an area of land

More from Merriam-Webster on boundary

Nglish: Translation of boundary for Spanish Speakers

Britannica English: Translation of boundary for Arabic Speakers


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