Synonyms for Partisan (same or very similar meaning)
WordNet sense 1 (a fervent and even militant proponent of something):
zealot, drumbeater
WordNet sense 2 (an ardent and enthusiastic supporter of some person or activity):
enthusiast, partizan
WordNet sense 3 (adhering or confined to a particular sect or denomination or party):
denominational
From the ODE community, based on WordNet
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