Verdi heroine (4)
I believe the answer is:
aida
'verdi heroine' is the definition.
(I've seen this in another clue)
This is the entire clue.
(Other definitions for aida that I've seen before include "Verdi's slave girl" , "slave of Covent Garden" , "Covent Garden production?" , "title role" , "Egyptian opera by 11 Down" .)