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

Skating is always about progression and pushing boundaries. Timothy Dahl, Popular Mechanics, "Big Air For a Higher Purpose," 6 Dec. 2018 To have the freedom to push those boundaries musically was beneficial in me having the confidence to also claim my own sexuality and project my ideas—and help others do it as well. Danny Murphy, Glamour, "If You Love 'Thank U, Next,' Just Wait Until You Meet Songwriter Tayla Parx," 3 Dec. 2018 Advisory Board Crystals’s founders Remington Guest and Heather Haber have often pushed the boundaries of retail through their releases with Slam Jam and Patron of the New and collaborations with the likes of Wikipedia and Nike. Steff Yotka, Vogue, "Want a Limited Edition Warhol-Inspired Tee? You’ll Have to Work for It," 15 Nov. 2018 Throughout his career, Dutch designer Joris Laarman has pushed the boundaries of what’s possible with a 3D printer. Liz Stinson, Curbed, "This 3D-printed steel bridge will be installed over an Amsterdam canal," 23 Oct. 2018 As Queen of the sartorial risk, Lady Gaga will take the reigns for the night alongside Harry Styles, also well-known for his love of flamboyancy and pushing the boundaries of typical menswear and gender through clothing. Lucy Wood, Marie Claire, "Lady Gaga Will Host Next Year's Met Gala With Harry Styles and Serena Williams," 10 Oct. 2018 She's also pushed the boundaries for women by becoming just the second world leader in modern times to give birth while in office. Nick Perry, Fox News, "Admired abroad, New Zealand leader faces hurdles at home," 24 Sep. 2018 But for Saudi Arabia, the relationship is also about security: defending its airspace, boundaries, and waters. Alex Ward, Vox, "Why the US won’t break up with Saudi Arabia over Jamal Khashoggi’s murder," 20 Nov. 2018 Comfort as the raison d’être of getting dressed, comfort with the idea of no boundaries, comfort as a permanent state of mind. Nancy Mcdonell, WSJ, "The Surprisingly Rich History of Women’s Underwear as Outerwear," 13 Nov. 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

12 Dec 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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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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a soft lustrous wool fabric with mohair

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