Puccini opera about an opera singer (5)
I believe the answer is:
tosca
'puccini opera about an opera singer' is the definition.
(I've seen this in another clue)
This is all the clue.
(Other definitions for tosca that I've seen before include "Coats off for a great opera" , "Puccini opera set in Rome" , "Luigi -, Italian playwright" , "Puccini's Rome opera" , "Opera heroine who leaps to her death" .)