The Collaborative International Dictionary of English v.0.48:
Maleficence \Ma*lef"i*cence\, n. [L. maleficentia. Cf. Malfeasance.] Evil doing, esp. to others. [1913 Webster]WordNet (r) 3.0 (2006):
maleficence n 1: doing or causing evil [ant: beneficence] 2: the quality or nature of being harmful or evil [syn: maleficence, mischief, balefulness] [ant: beneficence]