Emily Dickinson Lexicon

FA-NAT'IC, n.

A person affected by excessive enthusiasm, particularly on religious subjects; one who indulges wild and extravagant notions of religion, and sometimes exhibits strange motions and postures, and vehement vociferation in religious worship. Fanatics sometimes affect to be inspired or to have intercourse with superior beings. Fanatics are governed rather by imagination than by judgment. Stowe.