A follower or adherent of Flacius or the theological system of Flacianism.
From 'Flacian' plus the suffix '-ist' meaning a follower or practitioner; used in 16th-17th century Protestant theological controversies.
Flacianists were accused of basically being heretics by everyone—Catholics, mainstream Protestants, and other reformers—which meant their ideas survived mostly in obscure academic libraries until historians rediscovered them.
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