Leave Sunday drink and natter (6)
I believe the answer is:
gossip
'natter' is the definition.
('gossip' can be a synonym of 'natter')
'leave sunday drink' is the wordplay.
'leave' becomes 'go'.
'sunday' becomes 's'.
'drink' becomes 'sip' (I've seen this before).
'go'+'s'+'sip'='GOSSIP'
'and' acts as a link.
(Other definitions for gossip that I've seen before include "Loose malicious talk" , "Casual chit-chat" , "Rabbit" , "Idle and mildly malicious talk" , "Scandalous rumour" .)