Drinks for parties, if stirred (9)
I believe the answer is:
aperitifs
'drinks' is the definition.
(aperitif is a kind of drink)
'parties if stirred' is the wordplay.
'stirred' indicates anagramming the letters.
'parties'+'if'='partiesif'
'partiesif' anagrammed gives 'APERITIFS'.
'for' acts as a link.
(Other definitions for aperitifs that I've seen before include "Pre-dinner drinks" , "Starters" .)