n. 1 a border between two countries. b district on each side of this. 2 limits of attainment or knowledge in a subject. 3 US borders between settled and unsettled country. n frontiersman n.
n. 1 a border between two countries. b district on each side of this. 2 limits of attainment or knowledge in a subject. 3 US borders between settled and unsettled country. n frontiersman n.