Drab, dim (5)
I believe the answer is:
dingy
This clue is a double definition.
'drab' is the first definition.
(I know that drab can be written as dingy)
'dim' is the second definition.
(I've seen this before)
(Other definitions for dingy that I've seen before include "Dismal" , "Dark, grubby" , "Dark and rather dirty" , "Drab and depressing" , "Dim" .)