The Oxford Thesaurus An A-Z Dictionary of Synonyms - enthusiasmn.

1) eagerness, keenness, earnestness, fervour, avidity, zeal, excitement, passion, ardour, interest, relish, devotion, devotedness, gusto, exuberance, zest; fanaticism, mania, rage: No one matches her enthusiasm for grand opera. 2) rage, passion, craze; hobby, interest, pastime, diversion, amusement; Colloq fad: His current enthusiasm is acid rock.