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.
As if that wasn’t already plenty to look forward to, Wiseman also revealed that the ghost boundary will play a pretty big part in Season 6. — Katie Campione, Deadline, 24 July 2026 Plot The story unfolds over a few weeks in the summer of 1947 in Mano Majra, a fictional village near the Sutlej River lying along what will become the boundary between the two emerging countries. — Encyclopedia Britannica, 24 July 2026 The boundaries of the Historic Main Street Special Planning Area extend along Elk Grove Boulevard from Elk Grove Florin Road to Waterman Road. — Camryn Dadey, Sacbee.com, 23 July 2026 The irregular charcoal slate floor tiles throughout the main floor extend to the courtyard and around the swimming pool, blurring the boundaries between indoor and outdoor spaces. — Mark David, Robb Report, 23 July 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 26 Jul. 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

More from Merriam-Webster on boundary

Nglish: Translation of boundary for Spanish Speakers

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