a person motivated by irrational enthusiasm (as for a cause);
fanatic, fanatical, overzealous, rabid
marked by excessive enthusiasm for and intense devotion to a cause or idea;
My definition: Fanatic, Idiot, someone who stays up until 1 AM watching the Red Wings lose a game that should have resulted in a Stanley Cup win. Fanatics are characterized by an intraveneous Mountain Dew drip, dark circles under the eyes and an irritable disposition. They have been known to eat Penguins raw after a loss which tends to unnerve animal rights advocates everywhere.