proponent

Definitions

A person who advocates a theory, proposal, or project.

One who argues in favor of something; a supporter.

Examples

She is a vocal proponent of renewable energy and sustainable living.

The lead proponent of the new tax reform bill argued that it would stimulate economic growth.

Synonyms

advocate supporter champion exponent promoter apologist backer

Antonyms

opponent adversary critic detractor antagonist naysayer objector