'Shot' -- small drink for small talk (6)
I believe the answer is:
gossip
'small talk' is the definition.
('gossip' can be a synonym of 'small talk')
'shot small drink' is the wordplay.
'shot' becomes 'go' (I've seen this in other clues**).
'small' becomes 's' (abbreviation - e.g. clothes size).
'drink' becomes 'sip' (I've seen this before).
'go'+'s'+'sip'='GOSSIP'
'for' is the link.
(Other definitions for gossip that I've seen before include "Dish the dirt" , "Scandalous rumour" , "Busybody" , "Casual chit-chat" , "gas" .)