Drink Italian provided after a rep returned (8)
I believe the answer is:
aperitif
'drink' is the definition.
(I know that aperitif is a type of drink)
'italian provided after a rep returned' is the wordplay.
'italian' becomes 'it' (abbreviation for Italian).
'provided' becomes 'if' (eg 'provided it's sunny' means 'if it's sunny').
'after' says to put letters next to each other.
'returned' says the letters should be written backwards.
'rep' reversed gives 'per'.
'it'+'if'='itif'
'a'+'per'='aper'
'itif' after 'aper' is 'APERITIF'.
(Other definitions for aperitif that I've seen before include "What's drunk before a meal?" , "whistle-whetting drink" , "it's served before dinner" , "Appetite stimulant drink" , "appetizer" .)