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.

First, the fact that she felt a vested interest in how much money he gives to his kids crosses a boundary that would make most people uncomfortable.

From MarketWatch • Apr. 13, 2026

Maritime experts have said there is no legal argument for why Iran would be able to regulate commercial shipping on Oman’s side of the maritime boundary.

From The Wall Street Journal • Apr. 8, 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

They found that interactions between the magnetosphere and the solar wind at its outer boundary closely resemble processes observed at Jupiter.

From Science Daily • Apr. 3, 2026

The bad news was that the river destroyed many of the boundary markers, erasing all of the landmarks that told farmers which land was theirs to cultivate.

From "Zero: The Biography of a Dangerous Idea" by Charles Seife

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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