From The Collaborative International Dictionary of English v.0.48 [gcide]:
Malefic \Ma*lef"ic\, a. [L. maleficus: cf. F. mal['e]fique. See
Malefaction.]
Doing mischief; causing harm or evil; nefarious; hurtful.
[R.] --Chaucer.
[1913 Webster]
From WordNet (r) 3.0 (2006) [wn]:
malefic
adj 1: having or exerting a malignant influence; "malevolent
stars"; "a malefic force" [syn: malefic, malevolent,
malign, evil]