boundary

[ boun-duh-ree, -dree ]

noun

, plural bound·a·ries.

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. Compare six ( def 5 ).

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 Words From

• trans·bound·a·ry 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

Therefore, Championship matches are pushed to the edge of the square, which often results in a miniscule boundary on one side.

From BBC

"I didn't want to be seen to be making a fuss, especially early in my career, whereas now, I have way more boundaries of what I will or won't do," she said.

From BBC

"The particles adopt a certain orientation very early on, i.e. in the boundary layer between the water and the sediment. This alignment increases further within the first few millimetres of sediment," explains Kühn.

From Science Daily

“The boundaries between incident and alert need to be managed carefully,” he wrote in a blog post.

From BBC

The left-hander took 13 balls to get off the mark and struck two sweet boundaries off Smith before edging to give Smith a first Test wicket.

From BBC

Related Words

• barrier
• border
• borderline
• bounds
• confines
• edge
• frontier
• horizon
• line
• perimeter