From Treviso, a very Italian wine (5)
I believe the answer is:
soave
'italian wine' is the definition.
(I've seen this before)
'from treviso a very' is the wordplay.
'from' indicates the answer is hidden within the clue.
'SOAVE' is hidden within 'treviso a very'.
(Other definitions for soave that I've seen before include "Italian wine region" , "Drink" , "Italian dry white wine" , "White wine from NE Italy" , "Dry white wine from Verona" .)