Fair enough concealing intense anger (3)
I believe the answer is:
ire
'intense anger' is the definition.
(I've seen this before)
'fair enough concealing' is the wordplay.
'concealing' indicates a hidden word.
'IRE' is hidden in the letters of 'fair enough'.
(Other definitions for ire that I've seen before include "resentment" , "Anger, annoyance" , "heat" , "Displeasure" , "Fury" .)