Gossip here would be a concern, if head is replaced (6)
I believe the answer is:
natter
'gossip' is the definition.
(I know that gossip can be written as natter)
I cannot understand how the rest of the clue works.
Can you help me to learn more?
(Other definitions for natter that I've seen before include "Talk inconsequentially" , "idle talk" , "Chat - gossip" , "Chat away informally" , "Chit-chat" .)