The Collaborative International Dictionary of English v.0.48:

Sooty \Soot"y\, v. t.
   To black or foul with soot. [R.]
   [1913 Webster]

         Sootied with noisome smoke.              --Chapman.
   [1913 Webster]

The Collaborative International Dictionary of English v.0.48:

Sooty \Soot"y\, a. [Compar. Sootier; superl. Sootiest.] [AS.
   s?tig. See Soot.]
   1. Of or pertaining to soot; producing soot; soiled by soot.
      "Fire of sooty coal." --Milton.
      [1913 Webster]

   2. Having a dark brown or black color like soot; fuliginous;
      dusky; dark. "The grisly legions that troop under the
      sooty flag of Acheron." --Milton.
      [1913 Webster]

   Sooty albatross (Zool.), an albatross (Phoebetria
      fuliginosa) found chiefly in the Pacific Ocean; -- called
      also nellie.

   Sooty tern (Zool.), a tern (Sterna fuliginosa) found
      chiefly in tropical seas.
      [1913 Webster]

WordNet (r) 3.0 (2006):

sooty
    adj 1: of the blackest black; similar to the color of jet or
           coal [syn: coal-black, jet, jet-black, pitchy,
           sooty]
    2: covered with or as if with soot; "a sooty chimney"

Moby Thesaurus II by Grady Ward, 1.0:

23 Moby Thesaurus words for "sooty":
   besmirched, blotchy, dingy, dirty, dusty, fuliginous, grimy,
   grubby, grungy, messy, miry, muddy, murky, scruffy, slovenly,
   smirched, smirchy, smoky, smudgy, smutchy, smutty, snuffy,
   untidy