Revolting retreat over current leader (9)
I believe the answer is:
editorial
'revolting retreat' is the definition.
The answer and definition can be both related to communication as well as being singular nouns.
Maybe there's an association between them I don't understand?
'over current leader' is the wordplay.
'over' is a reversal indicator.
'current' becomes 'tide' (sea currents).
'leader' becomes 'orial' (I am not sure about this - if you are sure you should give a lot more credence to this answer).
'tide' back-to-front is 'edit'.
'edit'+'orial'='EDITORIAL'
Can you help me to learn more?
(Other definitions for editorial that I've seen before include "Article that states a newspaper's opinion" , "paper item" , "Paper's opinion piece" , "(Paper's) leader" , "considered view on paper" .)