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.

This remarkable effect occurs at a special condition known as the "Dirac point," where graphene sits at a boundary between being a metal and an insulator.

From Science Daily • Apr. 15, 2026

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

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

From The Wall Street Journal • Apr. 9, 2026

Smith starred again in the second wicket when Jamie Smith, having just driven Bamber to the cover boundary, attempted to repeat the shot and was caught by the keeper, diving in front of slip.

From BBC • Apr. 3, 2026

As it happened, the Fowl estate was the perfect location for a time-stop—isolated with a definite boundary.

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

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!