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 boundaryless (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

New technologies are pushing the boundaries of food preparation in microgravity. Chelsea Gohd, Scientific American, "The Space Station May Soon Smell like Fresh-Baked Cookies," 2 July 2019 On HBO’s boundary-pushing Euphoria, Dane plays Cal Jacobs, a married man with a secret. Maureen Lee Lenker,, "Eric Dane talks filming that 'intense' full-frontal scene in Euphoria," 17 June 2019 Independent, boundary-pushing festival includes theater, dance and poetry performances, film screenings and visual art at multiple venues throughout Over-the-Rhine. Luann Gibbs,, "Things to do in Cincinnati this week: June 10-16," 9 June 2019 Fans of boundary-breaking period dramas, rejoice: Gentleman Jack's first season didn't even finish before the show was renewed for a second go-around. Chloe Foussianes, Town & Country, "Gentleman Jack Is Returning for a Second Season. Here's What We Know So Far.," 4 June 2019 The game changing Pro Filt'r Foundation - now in 50 boundary-breaking shades. Chevaz Clarke, CBS News, "Rihanna is the world's richest female musician, Forbes reports," 4 June 2019 Best known for his then-scandalous, now-iconic pyramid outside Paris's Louvre museum, Pei designed numerous boundary-pushing structures around the world. Hadley Keller, House Beautiful, "Iconic Architect I. M. Pei Dies at 102," 17 May 2019 This city of Reims, with so many boundary-breaking women throughout its long and complicated history, is a fitting setting for a United States national team largely considered a trailblazer itself. Alicia Delgallo, Pro Soccer USA, "History of revolutionary women makes Reims fitting host for USWNT opening match," 2 Aug. 2018 In previous years, the Summit has touched upon themes of resiliency, personal growth and boundary-breaking careers. Stephanie Walden, USA TODAY, "The KPMG Women’s Leadership Summit aims to empower the next generation of women leaders," 19 June 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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Statistics for boundary

Last Updated

11 Jul 2019

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
: 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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More from Merriam-Webster on boundary

Rhyming Dictionary: Words that rhyme with boundary

Thesaurus: All synonyms and antonyms for boundary

Spanish Central: Translation of boundary

Nglish: Translation of boundary for Spanish Speakers

Britannica English: Translation of boundary for Arabic Speakers

Comments on boundary

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