Wine and veg being served? No! (10)
I believe the answer is:
chardonnay
'wine' is the definition.
(Chardonnay is an example)
'veg being served? no' is the wordplay.
'veg' becomes 'chard' (chard is a type of vegetable).
'being served?' becomes 'on' (I am not sure about this - if you are sure you should believe this answer much more).
'no' becomes 'nay' (archaic form 'no').
'chard'+'on'+'nay'='CHARDONNAY'
'and' is the link.
(Other definitions for chardonnay that I've seen before include "drink" , "Variety of white wine" , "White wine grape" .)