The Collaborative International Dictionary of English v.0.48:

Spatter \Spat"ter\, v. t. [imp. & p. p. Spattered; p. pr. &
   vb. n. Spattering.] [From the root of spit salvia.]
   1. To sprinkle with a liquid or with any wet substance, as
      water, mud, or the like; to make wet of foul spots upon by
      sprinkling; as, to spatter a coat; to spatter the floor;
      to spatter boots with mud.
      [1913 Webster]

            Upon any occasion he is to be spattered over with
            the blood of his people.              --Burke.
      [1913 Webster]

   2. To distribute by sprinkling; to sprinkle around; as, to
      spatter blood. --Pope.
      [1913 Webster]

   3. Fig.: To injure by aspersion; to defame; to soil; also, to
      throw out in a defamatory manner.
      [1913 Webster]

WordNet (r) 3.0 (2006):

spattered
    adj 1: covered with bright patches (often used in combination);
           "waves dabbled with moonlight"; "a blood-spattered room";
           "gardens splashed with color"; "kitchen walls splattered
           with grease" [syn: dabbled, spattered, splashed,
           splattered]

Moby Thesaurus II by Grady Ward, 1.0:

24 Moby Thesaurus words for "spattered":
   bespeckled, blotched, blotchy, dotted, dusted, freckle-faced,
   freckled, freckly, macular, maculate, maculated, peppered,
   powdered, specked, speckled, speckly, splashed, splattered,
   splotched, splotchy, spotted, spotty, sprinkled, studded