Part of benefit I repaid is returned in drink (8)
I believe the answer is:
aperitif
'drink' is the definition.
(aperitif is a kind of drink)
'part of benefit i repaid is returned' is the wordplay.
'part of' indicates the answer is hidden within the clue.
'is returned' says the letters should be written backwards.
'fitirepa' can be found hidden inside 'benefit i repaid'.
'fitirepa' backwards is 'APERITIF'.
'in' is the link.
(Other definitions for aperitif that I've seen before include "Pre-dinner drink" , "Appetite stimulant drink" , "alcohol before meal" , "Alcoholic drink to whet the appetite" , "Stimulant taken before meal" .)