It sounds like the height of resentment (5)
I believe the answer is:
pique
'resentment' is the definition.
(I've seen this in another clue)
'it sounds like the height' is the wordplay.
'it sounds like' shows a homophone (sound like).
'the height' becomes 'peak' ('peak' can be a synonym of 'height').
'peak' sounds like 'PIQUE'.
'of' acts as a link.
(Other definitions for pique that I've seen before include "Resentment at a slight" , "Slight reaction" , "Sudden irritation" , "Feeling of wounded pride" , "Feeling of resentment or indignation" .)