Definitions

1. adjective

covered or stained with soot or a similar dark substance

“The chimney sweep had a sooty face after working all day.”

2. noun

a dark or powdery deposit left by the burning of fossil fuels, especially coal

“The sooty residue on the windows needed to be cleaned.”

3. adverb

in a sooty manner or to a sooty extent

“The city was so sooty that it was hard to enjoy a walk in the park.”