Antonyms for the word "most extremist" range from moderate to centrist. A moderate takes a pragmatic and balanced approach, while a centrist is politically neutral, holding no extreme views on either side of the political spectrum. Other antonyms for "most extremist" include a peace-loving pacifist, compromiser, peacemaker, or conciliator who advocates for peaceful solutions and compromises to resolve conflicts. Furthermore, an open-minded pluralist who values multiple perspectives and diverse opinions can also be considered an antonym for "most extremist." Finally, someone who is conservative or conservative-leaning could be an antonym for "most extremist," as they tend to hold traditional views and promote stability and order over radical change.