Piedmont wine region (4)
I believe the answer is:
asti
'piedmont wine region' is the definition.
(I've seen this in another clue)
This is the entire clue.
(Other definitions for asti that I've seen before include "town in Italy" , "Piedmontese white wine" , "White wine named after a town in Piedmont" , "Italian white wine" , "Bubbly wine" .)