There are a number of synonyms that can be used to refer to Martin Luther King Jr. Some of the more common ones include civil rights leader, activist, preacher, and social justice warrior. Other possible synonyms could include advocate, reformer, orator, and peacemaker. No matter what synonym is used to describe Martin Luther King Jr., however, it is clear that he was a powerful and influential figure in the fight for civil rights and equality in America. His leadership and tireless efforts inspired millions to work towards a more just and equitable society, and his legacy lives on to this day.