Synonyms for Centrist (same or very similar meaning)
WordNet sense 1 (a person who takes a position in the political center):
moderate, moderationist, moderate
WordNet sense 2 (supporting or pursuing a course of action that is neither liberal nor conservative):
middle-of-the-road
WordNet sense 3 (of or belonging to neither the right nor the left politically or intellectually):
center
From the ODE community, based on WordNet
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