bound·ary | \ˈbau̇n-d(ə-)rē \
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 \ 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

The second is the porosity of urban boundaries: the creation and preservation of active in-between places that keep different urban realms connected rather than cut off from each other. Shlomo Angel, WSJ, "‘Building and Dwelling’ Review: A Manifesto for the Open City," 6 July 2018 The temple will sit on land just east of the Escondido city boundaries and west of the City of San Diego’s San Pasqual Agriculture Preserve on unincorporated property. J. Harry Jones,, "Hindu temple to be built in the San Pasqual Valley," 26 June 2018 Teens have the power of choice; parents have the power of boundaries. Eva Dwight, USA TODAY, "How do you get teens out of bed during the summer without fighting?," 25 June 2018 Plantings and a screening fence would be installed along most of the boundary between the property and the single-family homes north and east of the property, according to the application. Mikaela Porter, Courant Community, "Public Hearing Tuesday On Proposed Multifamily Development In West Hartford," 23 June 2018 Remove the loosened dirt with your hands and lay down two to three inches of fresh mulch along the edge of the boundaries before removing the string. Daniel Bortz, sacbee, "Four home-improvement jobs you can knock out," 15 June 2018 The trinity: The wild boar sausage ($8 per link) isn’t made in house, but continues the Black Board trend of pushing boundaries. Chuck Blount, San Antonio Express-News, "52 Weeks of BBQ: Black Board Bar B Q," 8 June 2018 Skiles' group first submitted its application with the city in December to carve out a new neighborhood council district out of the existing council's boundaries. Alejandra Reyes-velarde,, "Westwood students, community leaders vote to create new neighborhood council after heated debate," 26 May 2018 Scholarships can be used toward educational services or tuition at private or public schools outside of their home district's boundaries. Guest Columnist/,, "Thanks to the Ohio Autism Scholarship, our son receives therapies needed to succeed in the classroom: Robert and Amanda Fife (Opinion)," 29 Apr. 2018

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 2 + -ary entry 1

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Phrases Related to boundary

know no bounds/boundaries

Statistics for boundary

Last Updated

17 Oct 2018

Look-up Popularity

Time Traveler for boundary

The first known use of boundary was in 1598

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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

boundaries : unofficial rules about what should not be done : limits that define acceptable behavior


bound·ary | \ˈbau̇n-də-rē, 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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Comments on boundary

What made you want to look up boundary? Please tell us where you read or heard it (including the quote, if possible).


a state of commotion or excitement

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