Source : Webster's Revised Unabridged Dictionary (1913)

Malefic \Ma*lef"ic\, a. [L. maleficus: cf. F. mal['e]fique. See
   {Malefaction}.]
   Doing mischief; causing harm or evil; nefarious; hurtful.
   [R.] --Chaucer.

Source : WordNet®

malefic
     adj : having or exerting a malignant influence; "malevolent
           stars"; "a malefic force" [syn: {malevolent}, {malign},
            {evil}]