a city in the state of North Rhine-Westphalia in Germany; pop. 296,240 (1991). From 1949 until the reunification of Germany in 1990 Bonn was the capital of the Federal Republic of Germany 波恩(德国莱茵威斯特伐利亚州北部城市;1991年人口296,240;从1949年到1990年两德统一之前,波恩一直是德意志联邦共和国的首都)