·adj Of or relating to a frontier.
II. Frontier ·noun An Outwork.
III. Frontier ·vi To constitute or form a frontier; to have a frontier;
— with on.
IV. Frontier ·adj Lying on the exterior part; bordering; conterminous; as, a frontier town.
V. Frontier ·noun That part of a country which fronts or faces another country or an unsettled region; the marches; the border, confine, or extreme part of a country, bordering on another country; the border of the settled and cultivated part of a country; as, the frontier of civilization.