frontier

adj : on the American frontier; "one of the last real frontier

towns"; "hardships of frontier life" [syn: {frontier(a)}]

n 1: an international boundary or the area along such a boundary

2: a wilderness at the edge of a settled area of a country;

"the individualism of the frontier in Andrew Jackson's

day"

3: an undeveloped field of study; a topic inviting research and

development; "he worked at the frontier of brain science"