Balloonist's boast, maybe? (3,3)
I believe the answer is:
hot air
This could be a double definition.
'balloonist's' is the first definition.
Although both the answer and definition are singular nouns, I can't see how one could define the other.
'boast maybe?' is the second definition.
The definition and answer can be both related to communication as well as being singular nouns.
Maybe you can see an association between them that I can't see?
Can you help me to learn more?
(Other definitions for hot air that I've seen before include "Bluster" , "Boastful talk or balloon filler" , "Guff" , "Bombast or balloon filler" , "Bombastic talk or balloon elevator" .)