Gossip about a balloon (6)
I believe the answer is:
gasbag
This clue is a double definition.
'gossip' is the first definition.
(I've seen this before)
'a balloon' is the second definition.
(thesaurus)
'about' acts as a link.
(Other definitions for gasbag that I've seen before include "Person who talks too much - or a balloon" , "Idle chatterer" , "Excessive chatterer" , "One who natters a lot" , "Talkative person or filled balloon" .)