Foul seafood covering meal left by me (7)
I believe the answer is:
squalid
'foul' is the definition.
(thesaurus)
'seafood covering meal left by me' is the wordplay.
'seafood' becomes 'squid' (squid is a kind of seafood**).
'covering' indicates putting letters inside.
'left by' is a deletion indicator (word is left or abandoned by specified letters ).
'meal' with 'me' removed is 'al'.
'squid' going around 'al' is 'SQUALID'.
(Other definitions for squalid that I've seen before include "run down" , "Extremely dirty" , "Dirty and repulsive" , "Slum-like" , "Dirty and neglected" .)