Pavarotti piece (4)
I believe the answer is:
aria
'pavarotti piece' is the definition.
(I've seen this in another clue)
This is all the clue.
(Other definitions for aria that I've seen before include "Operatic tune" , "Elaborate accompanied song for solo voice" , "Vocal solo in a cantata etc" , "Summertime perhaps" , "part of opera, maybe" .)