前沿

前沿	qián yán	(military) forward position / frontier; cutting-edge; forefront
前	qián	front / forward / ahead / first / top (followed by a number) / future / ago / before / BC (e.g. 前293年) / former / formerly
沿	yán	along / to follow (a line, tradition etc) / to carry on / to trim (a border with braid, tape etc) / border / edge