‘联姻’ literally combines ‘联’ (to join, unite) and ‘姻’ (marriage, marital relation), meaning ‘to form a marital alliance.’ Historically, it referred to strategic marriages between noble families, states, or clans to strengthen political ties, consolidate power, or end conflicts. Today, it’s used both literally—describing actual marriages arranged for social or diplomatic purposes—and figuratively, especially in business or international relations, to describe formal partnerships or mergers that resemble marriage alliances in their depth and mutual commitment.

The term carries a formal, often elevated register and implies intentionality, long-term cooperation, and shared interests. It appears frequently in historical narratives, news reports about corporate mergers, and discussions of cross-border collaborations. Unlike casual terms like ‘合作’ (cooperation), ‘联姻’ evokes solemnity, prestige, and structural integration—like two entities becoming ‘family’ through binding agreement.