heretic heretic /ˈhɛrətɪk/

noun

1. () A person who holds religious beliefs in conflict with the dogma of the Roman Catholic Church  ( misbeliever , religious outcast , heretic )
   a person who holds religious beliefs in conflict with the dogma of the Roman Catholic Church
   
2. A person who holds unorthodox opinions in any field (not merely religion)  ( heretic )
   a person who holds unorthodox opinions in any field (not merely religion)