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.

That growing buildup has prompted calls for TFA to be considered a potential planetary boundary threat.

From Science Daily • Jun. 9, 2026

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 is certainly no desire to ever see Travis Head cut another boundary.

From BBC • Jun. 3, 2026

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

From MarketWatch • May 23, 2026

Zeitoun was willing to respect that boundary, but at the same time his interest was piqued.

From "Zeitoun" by Dave Eggers

Vocabulary lists containing boundary

Human Geography - Middle School

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Human Geography - High School

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Political Geography - Middle School

Want to remember this word for good? Start your learning journey today with our library of interactive, themed word lists built by the experts at Vocabulary.com – we'll help you make the most of your study time!