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.

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

I don’t want to be the one to draw the boundary — I need their permission to draw a boundary between us.

From Los Angeles Times • May 11, 2026

The stock recently retested its prior breakout from a symmetrical triangle from last September, coinciding with the lower boundary of the current bullish inverse head-and-shoulders pattern.

From Barron's • May 8, 2026

They stood quite still, holding on to each other, gazing at the dense black boundary of the graveyard.

From "Harry Potter and the Deathly Hallows" by J.K. Rowling

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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