Singer displaying some ethereal tones (4)
I believe the answer is:
alto
'singer' is the definition.
(alto is a kind of singer)
'displaying some ethereal tones' is the wordplay.
'displaying' indicates a hidden word.
'ALTO' can be found hidden inside 'some ethereal tones'.
(Other definitions for alto that I've seen before include "Counter-tenor or contralto" , "Singing voice between tenor and soprano" , "Low female singing voice" , "Singing range" , "someone to sing" .)