bound·​ary ˈbau̇n-d(ə-)rē How to pronounce boundary (audio)
plural boundaries
: 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 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?
Recent Examples on the Web More than a third of the people on the commission calling for Cincinnati to sell assets and raise taxes to fix its finances don't live within the city's boundaries. The Enquirer, 11 Apr. 2024 On the other hand, Trump has tested boundaries and feuded with the judge who may determine his fate. Aysha Bagchi, USA TODAY, 11 Apr. 2024 However, her dad and I have noticed a tendency to push right up against a rule or boundary. Amy Dickinson, The Mercury News, 11 Apr. 2024 That part is your job and responsibility, after all — to manage your side of your friendships, to set your own priorities and boundaries, and to communicate clearly. Carolyn Hax, Washington Post, 10 Apr. 2024 Read the full Cancer Daily Horoscope Leo (July 23 - August 22) Relational boundaries dissolve when the moon activates Venus and Neptune. USA TODAY, 31 Mar. 2024 This means setting boundaries, ensuring adequate rest and relaxation, engaging in regular physical activity, and nourishing the body with a balanced diet. Jia Rizvi, Forbes, 30 Mar. 2024 Hidalgo’s new address, in Arlington, is inside the Mansfield ISD boundary. Noah Alcala Bach, Fort Worth Star-Telegram, 29 Mar. 2024 The director, Sarah Benson, wanted someone dedicated to creating a space for the actors to feel safe, and free to set boundaries. Rachel Sherman, New York Times, 27 Mar. 2024

These examples are programmatically compiled from various online sources to illustrate current usage of the word 'boundary.' Any opinions expressed in the examples do not represent those of Merriam-Webster or its editors. Send us feedback about these examples.

Word History

First Known Use

1598, in the meaning defined above

Time Traveler
The first known use of boundary was in 1598

Dictionary Entries Near boundary

Cite this Entry

“Boundary.” Dictionary, Merriam-Webster, Accessed 22 Apr. 2024.

Kids Definition


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


plural boundaries
: a theoretical line that marks the limit of an area of land

More from Merriam-Webster on boundary

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