Grand __: wine classification (3)
I believe the answer is:
cru
'grand wine classification' is the definition.
(I've seen this in another clue)
This is all the clue.
(Other definitions for cru that I've seen before include "(Quality) vineyard; sounds like ship's men" , "French vineyard (and the wine from it)" , "French vineyard or group" , "Vineyard or group of them in France" , "Vintage, as applied to wine" .)