Answer: trustbuster

AnswerCrossword Clue
TRUSTBUSTERTeddy Roosevelt sobriquet
TRUSTBUSTERMonopolist's foe
TRUSTBUSTERTheodore Roosevelt's moniker
TRUSTBUSTERRely on comic Keaton?
trustbusterA person or agency employed to enforce antitrust legislation
trustbustera person who works for or achieves the breakup of business trusts, eg by legislation