Mephistopheles. One of the seven chief devils in the old demonology, the second of the fallen archangels, and the most powerful of the infernal legions after Satan. He figures in the old legend of Dr. Faustus as the familiar spirit of that magician. To modern readers he is chiefly known as the cold, scoffing, relentless fiend of Goethe's "Faust," and the attendant demon (Mephistophilis) in Marlowe's "Faustus."