[1] : The Collaborative International Dictionary of English v.0.48

mephistophelean \meph`istophe"lean\, mephistophelian
\meph`istophe"lian\? or ?, prop. a.
   pertaining to, or resembling, the devil mephistopheles, "a
   crafty, scoffing, relentless fiend;" devilish in character or
   aspect; crafty; showing cunning or ingenuity or wickedness;
   as, a mephistophelean glint in his eye.

   syn: devilish, diabolic, diabolical, mephistophelean.
        1913 webster

[2] : WordNet (r) 2.0

mephistophelean
     adj : showing the cunning or ingenuity or wickedness typical of a
           devil; "devilish schemes"; "the cold calculation and
           diabolic art of some statesmen"; "the diabolical
           expression on his face"; "a mephistophelian glint in
           his eye" syn: devilish, diabolic, diabolical, mephistophelian
see also:
devilish diabolic diabolical mephistophelian 

Mephistophelean >> M Words
Mephistophelean, definition of term: Mephistophelean
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