Caruso or Carreras (5)
I believe the answer is:
tenor
'caruso or carreras' is the definition.
(I've seen this in another clue)
This is all the clue.
(Other definitions for tenor that I've seen before include "Drift of thought" , "Eg, Placido Domingo" , "Caruso or Domingo" , "One singing" , "Male singer with high register" .)