n. 1. Great excitement for or interest in a subject or cause. 2. A source or cause of great excitement or interest. 3. Archaic a. Ecstasy arising from supposed possession by a god. b. Religious fanaticism. [Late Latin enthūsiasmus, from Greek enthousiasmos, from enthousiazein, to be inspired by a god, from entheos, possessed : en-, in; see EN-2 + theos, god; see dhēs- in the Appendix of Indo-European roots.] |
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