The part of a country which borders or faces another country or unsettled region.
The most advanced or recent version of something; leading edge.
To live as pioneers on frontier territory.
Pertaining to the middle voice.
Located in the middle; in between.
Central.
A centre, midpoint.
The part between the beginning and the end.
The middle stump.
The central part of a human body; the waist.
The middle voice.