noun bound·ary \ˈban-d(ə-)rē\

: 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

plural bound·aries

Full Definition of BOUNDARY

:  something that indicates or fixes a limit or extent
bound·ary·less \-ləs\ adjective
bound·ary·less·ness noun

Examples of BOUNDARY

  1. Those two trees mark the boundary of our property.
  2. The river forms the country's western boundary.
  3. at the boundary between fact and fiction
  4. You need to set boundaries with your children.
  5. Did he violate the boundaries of the doctor-patient relationship?

Origin of BOUNDARY

2bound + 1-ary
First Known Use: 1598

Rhymes with BOUNDARY

BOUNDARY Defined for Kids


noun bound·ary \ˈban-də-rē, ˈban-drē\
plural bound·aries

Definition of BOUNDARY for Kids

:  something that points out or shows a limit or end :  a dividing line


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