energumen
(ˌɛnəˈɡjuːmɛn) n1. (Alternative Belief Systems) a person thought to be possessed by an evil spirit
2. a fanatic or zealot
[C18: via Late Latin from Greek energoumenos having been worked on, from energein to be in action, from energos effective; see energy]
Collins English Dictionary – Complete and Unabridged, 12th Edition 2014 © HarperCollins Publishers 1991, 1994, 1998, 2000, 2003, 2006, 2007, 2009, 2011, 2014