Fruit goes off; covering goes off (8)
I believe the answer is:
goosegog
'fruit' is the definition.
(I've seen this before)
'goes off covering goes off' is the wordplay.
'goes off' becomes 'goog' (I can't explain this - if you can you should give a lot more credence to this answer).
'covering' is an insertion indicator.
'off' is an anagram indicator.
'goes' is an anagram of 'sego'.
'goog' placed around 'sego' is 'GOOSEGOG'.
(Other definitions for goosegog that I've seen before include "Hairy-skinned fruit (informal)" , "one might be taken for a fool" .)