fed·e·ra·tion /ˌfedəˈreɪʃən/ AWL noun 2 [countableC]PPG a group of states that have joined together to form a single group 联邦 the Russian Federation 俄罗斯联邦
3. [uncountableU]PPGSSO when groups of people, states etc join together to form a larger group 联邦;同盟