Irony to convey contempt (7)
I believe the answer is:
sarcasm
'irony to convey contempt' is the definition.
(I've seen this before)
This is the entire clue.
(Other definitions for sarcasm that I've seen before include "Gibe" , "Dry wit" , "Caustic remarks" , "Show of ironic contempt" , "Cutting wit" .)