Vower

Part of speech: noun

Definitions

1. A person who pledges or promises something solemnly, especially in a religious or ceremonial context
2. Someone who commits himself or herself to a course of action or belief through a formal oath or promise
3. An individual who binds himself or herself by swearing a solemn declaration or undertaking

Etymology: "Vower" is a plain formation: someone who vows, built from the verb "vow" with the agent suffix "-er" (as in "teacher" or "singer"). The word therefore names a person who makes a vow, and in that sense it is simply a transparent combination of the two parts, with no change in meaning from either.

Synonyms: promiser