The meaning of BOUNDARY is something that indicates or fixes a limit or extent. How to use boundary in a sentence.

BOUNDARY definition: a line or limit where one thing ends and another begins, or something that indicates such a line or limit. See examples of boundary used in a sentence.

BOUNDARY definition: 1. a real or imagined line that marks the edge or limit of something: 2. the limit of a subject or…. Learn more.

A boundary is a border and it can be physical, such as a fence between two properties, or abstract, such as a moral boundary that society decides it is wrong to cross.

boundary A line that delineates surface areas for the purpose of facilitating coordination and deconfliction of operations between adjacent units, formations, or areas.

The boundary of an area of land is an imaginary line that separates it from other areas.

something that indicates bounds or limits, as a line: A mountain range forms a natural boundary between the two countries.

Jan 20, 2026 · Noun boundary (plural boundaries) The dividing line or location between two areas.

Definition of boundary. English dictionary and integrated thesaurus for learners, writers, teachers, and students with advanced, intermediate, and beginner levels.

What are they and how to develop your own Setting healthy limits, or boundaries, in our lives allows us to take care of our health and well-being. In this resource, we’ll cover different types of boundaries, …