reformer
n.a person who works to improve a system, law, or organization by making changes to it. You use this for someone who wants to fix problems in society or government.
n.an individual who advocates for or works toward the improvement of a social, political, or religious system. Often associated with historical movements aimed at correcting institutional corruption or inefficiency.
“The reformer spent years fighting for better working conditions in factories.”
“As a dedicated educational reformer, she lobbied the government to provide free textbooks to every primary school student.”
“The 19th-century reformer faced significant opposition from established elites who benefited from the very systemic inequalities he sought to dismantle through legislative change.”
From reform + -er.
Etymology adapted from Wiktionary, available under CC BY-SA 4.0.