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.

Together, these goals “should nearly eliminate 90% of all untreated flows reaching the coast,” according to Chad McIntosh, U.S. commissioner of the International Boundary and Water Commission.

From The Wall Street Journal • May 4, 2026

Boundary information is supplied to the network, which then predicts the full molecular alignment field, including the shapes and positions of defects.

From Science Daily • Jan. 29, 2026

Thailand has always insisted its border dispute with Cambodia should be resolved bilaterally, without outside intervention, using a Joint Boundary Commission the two countries established 25 years ago.

From BBC • Aug. 20, 2025

The International Boundary and Water Commission says it’s not its job to collect the wastewater from unknown sources that flows into the Tijuana River.

From Los Angeles Times • Sep. 26, 2024

The landscape ahead began to look familiar—Crescent Beach, Boundary Bay.

From "The Son of Neptune" by Rick Riordan

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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