Simple Definition of boundary
: something (such as a river, a fence, or an imaginary line) that shows where an area ends and another area begins
: a point or limit that indicates where two things become different
boundaries : unofficial rules about what should not be done : limits that define acceptable behavior
Full Definition of boundaryplural
: something that indicates or fixes a limit or extent
boundarylessplay \-ləs\ adjective
Examples of boundary in a sentence
Those two trees mark the boundary of our property.
The river forms the country's western boundary.
at the boundary between fact and fiction
You need to set boundaries with your children.
Did he violate the boundaries of the doctor-patient relationship?
Origin and Etymology of boundary
2bound + 1-ary
First Known Use: 1598
Rhymes with boundary
BOUNDARY Defined for Kids
Definition of boundary for Students
: something that points out or shows a limit or end : a dividing line
Legal Definition of boundary
: a theoretical line that marks the limit of an area of land
Seen and Heard
What made you want to look up boundary? Please tell us where you read or heard it (including the quote, if possible).