Matrimony is the formal state of being married, or the ceremony of marriage itself. When two people enter into matrimony, they're making a serious, legal commitment to build a life together as a married couple.

The word has a formal, traditional feeling to it. You're more likely to hear “holy matrimony” in a wedding ceremony than to hear someone say “my parents entered into matrimony last year.” Most people would just say “got married” in casual conversation. But matrimony captures something important: marriage is an official bond recognized by law and, for many people, by religious traditions, with legal rights and responsibilities that go beyond the celebration or emotional connection.

In many wedding ceremonies, you'll hear the phrase “joined together in holy matrimony,” emphasizing that the couple is entering a sacred union.

When you see matrimony in writing, it usually suggests someone is treating marriage seriously and respectfully, whether they're describing a wedding ceremony, talking about marriage laws, or discussing the commitment two people make to each other.