Indeed upset when refused (6)
I believe the answer is:
denied
'refused' is the definition.
('deny' can be a synonym of 'refuse')
'indeed upset' is the wordplay.
'upset' indicates an anagram.
'indeed' anagrammed gives 'DENIED'.
'when' acts as a link.
(Other definitions for denied that I've seen before include "Refused to admit (the truth)" , "Refused to give (someone something)" , "Refused to admit and refused access to" , "Indeed (anag)" , "Contradicted" .)