Rubbish cover on Bentley in car storage (7)
I believe the answer is:
garbage
'rubbish' is the definition.
(both can mean refuse or trash)
'cover on bentley in car storage' is the wordplay.
'cover on' indicates taking the first letters (the letter which covers the rest of them up).
'in' is an insertion indicator.
'car storage' becomes 'garage' (I've seen this before).
The initial letter of 'bentley' is 'b'.
'b' put within 'garage' is 'GARBAGE'.
(Other definitions for garbage that I've seen before include "Food waste or trash" , "Worthless matter" , "'Refuse, rubbish (7)'" , "Unwanted stuff" , "Nonsense!" .)