frontier /ˈfrʌntjə/ n. ［c］ 1.边境，国境；边疆: close the frontier 封锁边境；a town (city) on the frontier 边境城镇(市) The soldiers guarded the frontier of the country. 战士们守卫边疆。  Sweden has frontiers with Norway and Finland. 瑞典同挪威、芬兰接壤。 2.新领域：advance the frontier of human knowledge 扩大人类知识的领域；at the frontier of space exploration 在太空探索的新领域