collective name for the chief gods of the pagan Scandinavian religion, from Old Norse plural of āss "god," from Proto-Germanic *ansu- (source also of Old High German ansi, Old English os, Gothic ans "god"), from PIE root *ansu- "spirit" (source also of first element in Ahura Mazda (q.v.)).
name of the mischievous fairy in "A Midsummer Night's Dream," in 16c. the name of a fairy of high repute (his disguised name was Robin Goodfellow or Friar Rush), also generally, "an elf, fairy, or sprite;" probably from Middle English pouke "devil, evil spirit" (c. 1300; early 13c. in place-names), from Old English puca, pucel "goblin," which is cognate with Old Norse puki "devil, fiend," a word of unknown origin (compare pug). Celtic origins also have been proposed.
1590s, Mephastophilus, the name of the evil spirit to whom Faust sold his soul in the old legend, from German (1587), a word of unknown origin. The older, Greek-like form is apparently a folk-etymology. According to the speculation of eminent Göthe scholar K.J. Schröer (1886) it is a compound of Hebrew mephitz "destroyer" + tophel "liar" (short for tophel sheqer, literally "falsehood plasterer;" see Job xiii.4). Klein writes that the names of devils in the Middle Ages "are in most cases derived from Hebrew." Related: Mephistophelian.