世交的英语杂个说

世交
1.friendship spanning two or more generations;2.old family friends

正当华代尔夫人进行投机的时候，德·坎特尔夫妇意外地发了财:这是德·坎特尔夫人的世交伏特莱克伯爵遗赠给她的一笔财产。
While Mme. Walter was carrying on her speculations, the de Cantels received a windfall in the form of a bequest from the late Count de Vaudrec, an old family friend of Mme. de Cantel.

a life time's friend