Contrary chatter? (8)
I believe the answer is:
converse
This clue is a double definition.
'contrary' is the first definition.
(synonyms)
'chatter?' is the second definition.
(I know that chatter is a more specific form of the action converse)
(Other definitions for converse that I've seen before include "Quite the opposite!" , "Discourse" , "Talk - opposite" , "Communicate with" , "Opposing" .)