The Collaborative International Dictionary of English v.0.48:

Scornful \Scorn"ful\, a.
   1. Full of scorn or contempt; contemptuous; disdainful.
      [1913 Webster]

            Scornful of winter's frost and summer's sun.
                                                  --Prior.
      [1913 Webster]

            Dart not scornful glances from those eyes. --Shak.
      [1913 Webster]

   2. Treated with scorn; exciting scorn. [Obs.]
      [1913 Webster]

            The scornful mark of every open eye.  --Shak.
      [1913 Webster]

   Syn: Contemptuous; disdainful; contumelious; reproachful;
        insolent.
        [1913 Webster] -- Scorn"ful*ly, adv. --
        Scorn"ful*ness, n.
        [1913 Webster]

WordNet (r) 3.0 (2006):

scornful
    adj 1: expressing extreme contempt [syn: contemptuous,
           disdainful, insulting, scornful]

Moby Thesaurus II by Grady Ward, 1.0:

34 Moby Thesaurus words for "scornful":
   abjuratory, arrogant, clannish, cliquish, contemptuous,
   contumelious, declinatory, deprecative, derisive, derisory,
   despising, disdainful, dismissive, disparaging, exclusive, haughty,
   high-handed, mocking, overweening, rejective, renunciative,
   scoffing, sneering, snide, sniffy, snobbish, snobby, snooty,
   snotty, supercilious, superior, toploftical, toplofty, withering