(boundaries)
1.
The boundary of an area of land is an imaginary line that separates it from other areas.
...the Bow Brook which forms the western boundary of the wood...
Drug traffickers operate across national boundaries.
= border, frontier
N-COUNT: oft N of/between n
2.
The boundaries of something such as a subject or activity are the limits that people think that it has.
The boundaries between history and storytelling are always being blurred and muddled.
...extending the boundaries of press freedom.
N-COUNT: usu pl, oft N of/between n