"centrist" in the noun sense
1. centrist, middle of the roader, moderate, moderationist
a person who takes a position in the political center
"centrist" in the adjective sense
1. centrist, middle-of-the-road
supporting or pursuing a course of action that is neither liberal nor conservative
Source: WordNet® (An amazing lexical database of English)
Princeton University "About WordNet®."
WordNet®. Princeton University. 2010.
View WordNet® License