Source : Webster's Revised Unabridged Dictionary (1913)

Wickedly \Wick"ed*ly\, adv.
   In a wicked manner; in a manner, or with motives and designs,
   contrary to the divine law or the law of morality; viciously;
   corruptly; immorally.

         I have sinned, and I have done wickedly. --2 Sam. xxiv.
                                                  17.

Source : WordNet®

wickedly
     adv : in a wicked evil manner; "act wickedly"; "grin evilly" [syn:
            {evilly}]