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.

Rather than risk crossing a murky boundary, many educators avoided discussing religion altogether.

From The Wall Street Journal • Apr. 9, 2026

It narrates the bittersweet adventures of the titular astronomer and his surveyor sidekick who carved the boundary separating slave states from free.

From Los Angeles Times • Apr. 9, 2026

There was a crater, he said, on the nearside-farside boundary - a bright spot to the northwest of Glushko crater.

From BBC • Apr. 7, 2026

This area is separated from the rest of the cell by an actin-myosin condensate barrier, which acts like a physical boundary and directs proteins to the advancing edge.

From Science Daily • Apr. 1, 2026

The Retrieval Squad put down just inside the boundary and began an immediate scan for possible hostiles.

From "Artemis Fowl" by Eoin Colfer

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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