自愿联合

【法】 voluntary union

自愿的英语翻译：

lief; volunteer
【法】 unconstraint

联合的英语翻译：

unite; ally; connect; link; associate; band; joint; combination; federation
linkage; union; alliance
【计】 uniting
【化】 union
【医】 association; coadunation; coadunition; symphysis; syndesis; union
【经】 associate; coalition; combination; consolidate; consortium; fusion
union