Definition of: vow

(vou) noun
1. A solemn promise to God or to a deity or saint to perform some act or make some gift or sacrifice: generally made in a time of peril or need, and on the condition of the fulfillment of some petition or in return for special divine favor: the vow of Jephthah.
2. A solemn engagement to adopt a certain course of life, pursue some end, observe some moral precept, or surrender oneself to a higher life of holiness; also, a pledge of faithfulness: marriage vows.
3. A solemn and emphatic affirmation. See synonyms under OATH.
—to take vows To enter a religious order.
—v.t.
1. To promise solemnly; especially, to promise to God or to some deity.
2. To declare with assurance or solemnity.
3. To make a solemn promise or threat to do, inflict, etc.
—v.i.
4. To make a vow. [<AF vu, OF vo, vou <L votum. Doublet of VOTE.]
—vow′er noun