The Collaborative International Dictionary of English v.0.48:

cussed \cus"sed\ (c[u^]s"[e^]d), adj.
   stubbornly persistent in wrongdoing; obstinate. [Slang or
   Colloq., U. S.]

   Note: [Narrower terms: unregenerate (vs. regenerate),
         unregenerated]

   Syn: obdurate, obstinate, perverse, unrepentant.
        [WordNet 1.5]

WordNet (r) 3.0 (2006):

cussed
    adj 1: stubbornly persistent in wrongdoing [syn: cussed,
           obdurate, obstinate, unrepentant]