With little hesitation supporter Grace ends showing resentment (7)
I believe the answer is:
umbrage
'resentment' is the definition.
(thesaurus)
'with little hesitation supporter grace ends' is the wordplay.
'with' means one lot of letters go next to another.
'little hesitation' becomes 'um'.
'supporter' becomes 'bra' (a bra gives support to breasts).
'ends' suggests removing the centre.
'grace' with its centre removed is 'ge'.
'um' next to 'bra' is 'umbra'.
'umbra'+'ge'='UMBRAGE'
'showing' acts as a link.
(Other definitions for umbrage that I've seen before include "The sulks" , "Offence that's usually taken" , "Take this to feel offence" , "Feeling of offence" , "Feeling of anger caused by being offended" .)