vower

noun

1. a solemn promise or pledge, esp. one made to God or a god, dedicating oneself to an act, service, or way of life
2. a solemn promise of love and fidelity: marriage vows
3. a solemn affirmation or assertion

transitive verb

1. to promise solemnly
2. to make a solemn resolution to do, get, etc.
3. to declare emphatically, earnestly, or solemnly

intransitive verb