Yes, vest is a Scrabble word!

Verb

1. Provide with power and authority

2. Place (authority, property, or rights) in the control of a person or group of persons

3. Become legally vested

4. Clothe oneself in ecclesiastical garments

5. Clothe formally; especially in ecclesiastical robes

Noun

1. A man's sleeveless garment worn underneath a coat

2. A collarless men's undergarment for the upper part of the body