enthusiast

enthusiast is a   Noun

Definition:

[1] One moved or actuated by enthusiasm; as: (a) One who imagines himself divinely inspired, or possessed of some special revelation; a religious madman; a fanatic. (b) One whose mind is wholly possessed and heated by what engages it; one who is influenced by a peculiar; fervor of mind; an ardent and imaginative person. Enthusiasts soon understand each other. W. Irving.

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