One who sings in private, normally (5)
I believe the answer is:
tenor
'one who sings' is the definition.
The answer is a person as well as being a singular noun. This is suggested by the definition.
'in private normally' is the wordplay.
'in' indicates a hidden word.
'TENOR' can be found hidden inside 'private normally'.
Can you help me to learn more?
(Other definitions for tenor that I've seen before include "theme" , "Singer; drift" , "Pavarotti, maybe" , "Male singing voice of high pitch" , "Male voice of high pitch, like Luciano" .)