boundary

[boun-duh-ree, -dree]

noun

plural

boundaries 

1. a line or limit where one thing ends and another begins, or something that indicates such a line or limit.

   The ancient wall still serves as the city's outer boundary.

   These studies straddle the boundaries between computational and social sciences.

   Synonyms: limit, bound

2. a limit that separates acceptable behavior from unacceptable behavior.

   I'm just looking for a partner who can respect my boundaries.

   Guiding children toward responsible money habits requires setting boundaries.

3. Also called frontier. Mathematics.,  the collection of all points of a given set having the property that every neighborhood of each point contains points in the set and in the complement of the set.

4. Cricket.,  a hit in which the ball reaches or crosses the boundary line of the field on one or more bounces, counting four runs for the batsman.

boundary

/ -drɪ, ˈbaʊndərɪ /

noun

1. something that indicates the farthest limit, as of an area; border

2. cricket

   1. the marked limit of the playing area

   2. a stroke that hits the ball beyond this limit

   3. the four runs scored with such a stroke, or the six runs if the ball crosses the boundary without touching the ground

Other Word Forms

• transboundary adjective

Word History and Origins

Origin of boundary¹

First recorded in 1620–30; bound ³ + -ary

Synonym Study

Boundary, border, frontier share the sense of that which divides one entity or political unit from another. Boundary, in reference to a country, city, state, territory, or the like, most often designates a line on a map: boundaries are shown in red. Occasionally, it also refers to a physical feature that marks the agreed-upon line separating two political units: The Niagara River forms part of the boundary between the United States and Canada. Border is more often used than boundary in direct reference to a political dividing line; it may also refer to the region (of, for instance, a country) adjoining the actual line of demarcation: crossing the Mexican border; border towns along the Rio Grande. Frontier may refer to a political dividing line: crossed the Spanish frontier on Tuesday. It may also denote or describe the portion of a country adjoining its border with another country ( towns in the Polish frontier ) or, especially in North America, the most remote settled or occupied parts of a country: the frontier towns of the Great Plains. Frontier, especially in the plural, also refers to the most advanced or newest activities in an area of knowledge or practice: the frontiers of nuclear medicine.

Example Sentences

I think it’s just allowed me to have more boundaries.

Read more on Los Angeles Times

Their top five batters failed to reach double figures and it took them 15 overs to find their first boundary.

Read more on Barron's

But the exciting thing for me is that I’ve always wanted to break new boundaries.

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Each of the book’s seven chapters is titled “The Edge of” something: the known world, knowledge, survival, culture, humanity, boundaries, the universe.

Read more on The Wall Street Journal

Ghosh was irresistible, hitting 58 from 33 balls after the fall of the seventh wicket, and showing herself to be a 360 player with boundaries all around the ground.

Read more on BBC

Related Words

• barrier 
• border 
• borderline 
• bounds 
• confines www.thesaurus.com
• edge 
• frontier 
• horizon 
• line 
• perimeter