boundary

C1 Topic:Places & Geography

US /ˈbaʊndəɹi/ UK /ˈbaʊndɹi/ See IPA manual

Freq #11794

Meanings

1

noun
A line that marks where one area ends and another begins.

The river forms the boundary between the two countries.
2

noun
A limit on what is acceptable in someone's behaviour, privacy, or personal life.

I didn't mean to cross a boundary by messaging my boss on the weekend.
3

noun
The furthest limit of what is known or possible in a field.

Their research pushes the boundaries of modern science.

Thesaurus

Synonyms

1 noun · a line that marks where one... bound

3 noun · the furthest limit of what... bound

Word family

Forms boundaries

Derived forms boundariedboundarilessboundarylesscoboundarygeoboundaryisoboundarytransboundary

Related forms border bound confinefladryfrontier

Appears in

Phrases (1)

See all

outer boundary
the edge marking the outside limit of an area or object

Adjective + noun

Etymology

From bound + -ary, Old French, from Latin.

Topics

Places & Geography Word Formation & Derivatives

External links

# boundary

**Type:** Word
**Level:** C1
**Part of speech:** noun
**IPA (US):** /ˈbaʊndəɹi/
**IPA (UK):** /ˈbaʊndɹi/
**Frequency rank:** 11794

## Meanings
1. A line that marks where one area ends and another begins.
2. A limit on what is acceptable in someone's behaviour, privacy, or personal life.
3. The furthest limit of what is known or possible in a field.

## Examples
- The river forms the boundary between the two countries.
- I didn't mean to cross a boundary by messaging my boss on the weekend.
- Their research pushes the boundaries of modern science.

## Derived Forms
- boundaried
- boundariless
- boundaryless
- coboundary
- geoboundary
- isoboundary
- transboundary

## Related Forms
- border
- bound
- confine
- fladry
- frontier

## Etymology
From bound + -ary, Old French, from Latin.

## AI Etymology
Boundary is from bound + -ary, Old French, from Latin. The analysis is mainly morphological: the modern nominal form is built from the named base and affix. Current senses include a line that marks where one area ends and another begins, a limit on what is acceptable in someone's behaviour, privacy, or personal life, and the furthest limit of what is known or possible in a field. The wider family includes derived forms such as boundaried, boundariless, boundaryless, coboundary, and geoboundary and related words such as border, bound, confine, fladry, and frontier.

## Topics
- Places & Geography
- Word Formation & Derivatives

markdown