A person who anathematizes; someone who pronounces curses or condemnations, especially a religious authority who excludes people from the church.
From anathematize plus the suffix -er, which creates a noun meaning 'one who performs the action.' The suffix -er is one of English's most productive agent noun suffixes.
Medieval bishops were powerful anathematizers—their curse could theoretically doom someone's eternal soul, which made them among the most feared people in Europe.
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