Definition

Etymology: From about 1525, "insane person", from Latin fanaticus, "mad, enthusiastic, inspired by a god," originally, "pertaining to a temple," from fanum "temple," related to festus "festive". The current sense of "extremely zealous", especially in religion, is first attested in 1647. The noun is from 1650, originally in a religious sense, of nonconformists.


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