Having gone off again, came back (8)
I believe the answer is:
returned
'came back' is the definition.
('return' can be a synonym of 'come back')
'having gone off again' is the wordplay.
I cannot really see how this works, but
'gone' could be 'turned' (turning is a kind of going) and 'turned' is found in the answer.
'again' could be 're' (prefix meaning 'again') and 're' is found within the answer.
This accounts for all the letters.
This may be the basis of the clue (or it may be nonsense).
Can you help me to learn more?
(Other definitions for returned that I've seen before include "Went, came or brought back" , "Honoured by the electorate" , "Came back - voted in" , "dishonoured by the bank" , "Went, came or gave back" .)