| Doer 1. (v. t. & i.) One who does; one performs or executes; one who is wont and ready to act; an actor; an agent. 2. (v. t. & i.) An agent or attorney; a factor. Thesaurus Entries activist, ball of fire, beaver, big-time operator, bustler, busy bee, eager beaver, enthusiast, go-getter, human dynamo, hustler, live wire, man of action, man of deeds, militant, new broom, operator, political activist, powerhouse, take-charge guy, wheeler-dealer, winner |