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

diabolic \di`abol"ic\, diabolical \di`abol"ical\, a. l.
   diabolicus, gr. ? devilish, slanderous: cf. f. diabolique.
   see devil.
   1. pertaining to the devil; resembling, or appropriate, or
      appropriate to, the devil; befitting hell or satan;
      devilish; infernal; impious; as, a diabolic or diabolical
      temper or act; the diabolical expression on his face;
      fires lit up a diabolic scene. "diabolic power." --milton.
      "the diabolical institution." --motley.

   syn: devilish, mephistophelian, mephistophelean.
        1913 webster

   2. showing a wicked cunning or ingenuity; as, the cold
      calculation and diabolic art of some statesmen.

   syn: devilish, mephistophelian, mephistophelean.
        wordnet 1.5

   3. extremely evil or cruel; atrocious; outrageously wicked;
      as, diabolical sorcerers under the influence of devils;
      diabolical torturers taking pleasure in their craft.

   syn: demonic, fiendish, hellish, infernal, nefarious,
        satanic.
        1913 webster + wordnet 1.5 -- di`abol"ically,
        adv. -- di`abol"icalness, n.
see also:
devil di`abol"ically di`abol"icalness 

[2] : WordNet (r) 2.0

diabolically
     adv : as a devil; in an evil manner; "his writing could be
           diabolically satiric" syn: devilishly, fiendishly
see also:
devilishly fiendishly 

Diabolically >> D Words
Diabolically, definition of term: Diabolically
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