A vow (Lat. votum, vow, promise; see vote) is a promise or oath.
A vow is used as a promise, a promise solemn rather than casual.
Marriage vows are binding promises each partner in a couple makes to the other during a wedding ceremony. Marriage customs have developed over history and keep changing as human society develops. In earlier times and in most cultures the consent of the partners has not had the importance now attached to it, at least in Western societies and in those they have influenced. Protestants, for instance, consider marriage vow as an unchangeable divine law since it needs not only "conciliar assertion" but also the support of the Scripture, making marriage a form of divine ordinance.
Within the world of monks and nuns, a vow is sometimes a transaction between a person and a deity, where the former promises to render some service or gift, or devotes something valuable to the deity's use. The vow is a kind