From The Collaborative International Dictionary of English v.0.48 [gcide]:
Enthusiast \En*thu"si*ast\, noun [Gr. ?: cf. F. enthousiaste.] 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.
From WordNet (r) 3.0 (2006) [wn]:
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