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 Giving serious 2012-era Beat Scene vibes, the album is smartly experimental, favoring boundary-expanding productions over easy to access melodies or traditional cut and paste soundscapes. Katie Bain, Billboard, 4 June 2021 So, the music and fitness industries grew closer together in a lot of ways — whether through Peloton’s boundary-pushing partnerships or the Calm app’s experimental artist deals — but Optimized fills a hole for music workers specifically. Samantha Hissong, Rolling Stone, 24 May 2021 Trump’s social media megaphone during his presidency helped transform Facebook, as the company sought ways to survive a hostile political climate and accommodate the boundary-pushing president. Washington Post, 4 May 2021 That early boundary-pushing seemed to lend an air of inevitability to the governor, a sense that he had only been strengthened and emboldened by committing unmistakable good-government sins and facing no lasting consequences. New York Times, 13 Apr. 2021 Many said that the decision merely kicked the can back to the social network and did not provide clear guidance for the treatment of boundary-pushing politicians., 5 May 2021 The team was tight, cohered by catharsis, and an invisible boundary separated those who had hoisted the chalice from those who hadn’t. New York Times, 4 May 2021 Or the land could be annexed into neighboring Oviedo after it is removed from Seminole’s rural boundary, where development is restricted to at least one home per five acres. Martin E. Comas,, 20 Apr. 2021 With King Crimson, Robert has written music that has to be held within an invisible boundary to stop the train coming off the tracks. David Browne, Rolling Stone, 24 Mar. 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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Statistics for boundary

Last Updated

11 Jun 2021

Cite this Entry

“Boundary.” Dictionary, Merriam-Webster, Accessed 15 Jun. 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


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