Using mocking irony (9)
I believe the answer is:
sarcastic
'using mocking irony' is the definition.
(I've seen this before)
This is all the clue.
(Other definitions for sarcastic that I've seen before include "Using mocking wit" , "Cruelly ironical" , "Using mocking irony" , "Contemptuous" , "Derisive" .)