Dirty or squalid (6)
I believe the answer is:
sordid
I believe this is a double definition.
'dirty' is the first definition.
(I know that dirty can be written as sordid)
'squalid' is the second definition.
(I know that squalid can be written as sordid)
(Other definitions for sordid that I've seen before include "Squalid or ignorable" , "'Seamy, seedy (6)'" , "Squalid, not honourable" , "Dirty, mean" , "Squalid and disgusting" .)