1N-COUNT 大公(旧时西班牙的最高爵位) In the past, a grandee was a Spanish prince of the highest rank. 大公(旧时西班牙的最高爵位)
2N-COUNT 大人物;显贵;(尤指)政要 You can refer to someone, especially a politician, who is upper class and has a lot of influence as a grandee . 大人物;显贵;(尤指)政要 [mainly British]
He is a former defence secretary of the United States and a grandee of the Democratic Party.