Irritable talent up for renewal (8)
I believe the answer is:
Here is my best explanation:
'irritable' is the definition.
('petulant' can be a synonym of 'irritable')
'talent up for renewal' is the subsidiary indication.
'talent up' anagrams to 'petulant'.
However, I am not sure how the anagram is indicated.
(Other definitions for petulant that I've seen before include "Peevish, inclined to complain", "Fractious, pouty", "Pouting", "Peevish, surly", "Sulky", "Querulous and demanding", "Fractious, peevish", "Sullen in a peevish way", "peevish impatience" and "Easily irritated".)