(~s)
1.
The ~ between two things is an area which contains features from both of these things so that it is not possible to say that it belongs to one or the other.
...on the ~ between sleep and waking.
N-SING: usu with supp
2.
The area of land close to the border between two countries or major areas can be called the ~s.
...Lebanon’s southern ~s.
N-COUNT: usu pl