Character change for a GI (6)
I believe the answer is:
figaro
'character' is the definition.
(I have seen 'Operatic character ' mean 'figaro' so perhaps 'character' could also mean 'figaro')
'change for a gi' is the wordplay.
'change' indicates an anagram.
'for'+'a'+'gi'='foragi'
'foragi' anagrammed gives 'FIGARO'.
(Other definitions for figaro that I've seen before include "hairdresser" , "The Barber of Seville" , "Operatic bridegroom" , "Le -, French paper" , "Wily barber" .)