Answer: sooted

AnswerCrossword Clue
SOOTEDLike Santa's suit, probably
SOOTEDCovered with coal dust.
SOOTEDBesmudged.
SOOTEDSmudged
SOOTEDLike an active chimney sweep
SOOTEDCoated with black, maybe
sootedto coat or cover with soot
sootedSOOT, to cover with a residue of burning