Dirty, like a chimney (5)
I believe the answer is:
sooty
I believe this is a double definition.
'dirty' is the first definition.
(thesaurus)
'like a chimney' is the second definition.
(I've seen this in another clue)
(Other definitions for sooty that I've seen before include "Covered in black dust" , "4 [BEAR]" , "Hand-puppet TV bear" , "TV glove puppet" , "black marks" .)