Definitions

boundary

[boun-duh-ree, -dree] / ˈbaʊn də ri, -dri /

NOUN

outer limit

Synonyms

STRONGEST

barrier border borderline bounds confines edge frontier horizon line perimeter

STRONG

ambit beginning borderland brink circumference circumscription compass end environs extent extremity frame fringe hem limits march margin mark mere mete outline outpost pale periphery precinct purlieus radius rim side skirt terminal termination terminus verge

WEAK

abuttals line of demarcation

Antonyms

STRONGEST

center inside interior middle

STRONG

opening start

WEAK

minimum

Example Sentences

Examples are provided to illustrate real-world usage of words in context. Any opinions expressed do not reflect the views of Dictionary.com.

In Rhode Island, a case has been ongoing for three years over a law that moved the boundary of a public beach further inland.

From The Wall Street Journal • Jun. 9, 2026

There was a run of 18 deliveries without a boundary and India could not get going again.

From BBC • May 30, 2026

The boundary at which gaming ends and AI begins has always been blurry.

From MarketWatch • May 23, 2026

"For the first time, we could trace the boundary between the gas residing in galaxies and the material contained within the cosmic web through direct measurements."

From Science Daily • May 16, 2026

Holmes acquired a ticket to a village called Englewood in the town of Lake, a municipality of 200,000 people that abutted Chicago’s southernmost boundary.

From "The Devil in the White City" by Erik Larson

Vocabulary lists containing boundary

Human Geography - Middle School

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Human Geography - High School

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Political Geography - Middle School

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