Source : Webster's Revised Unabridged Dictionary (1913)

Maleficence \Ma*lef"i*cence\, n. [L. maleficentia. Cf.
   {Malfeasance}.]
   Evil doing, esp. to others.

Source : WordNet®

maleficence
     n 1: doing or causing evil [ant: {beneficence}]
     2: the quality or nature of being harmful or evil [syn: {mischief},
         {balefulness}] [ant: {beneficence}]