Bitter denunciation (8)
I believe the answer is:
diatribe
'bitter denunciation' is the definition.
(I've seen this in another clue)
This is all the clue.
(Other definitions for diatribe that I've seen before include "A prolonged tirade or abusive speech" , "Stream of invective" , "Passionate words" , "Bitter words" , "provoking verbal onslaught" .)