Fainted, perhaps, but recalcitrant (7)
I believe the answer is:
defiant
'recalcitrant' is the definition.
(similar in meaning)
'fainted perhaps' is the wordplay.
'perhaps' indicates an anagram.
'fainted' is an anagram of 'DEFIANT'.
'but' is the link.
(Other definitions for defiant that I've seen before include "Mutinous" , "Fainted, being rebellious" , "Openly resisting" , "Uncooperative" , "Boldly resistant -- fainted (anag)" .)