Hum uplifting bit of Beethoven or Debussy (5)
I believe the answer is:
drone
'hum' is the definition.
(I have seen 'Continuous hum ' mean 'drone' so perhaps 'hum' could also mean 'drone')
'uplifting bit of beethoven or debussy' is the wordplay.
'uplifting' shows that the letters should be reversed in order.
'bit of' says the answer is hidden in the clue.
'enord' is hidden in the letters of 'beethoven or debussy'.
'enord' in reverse letter order is 'DRONE'.
(Other definitions for drone that I've seen before include "Low hum; parasite" , "talk long and tediously" , "Continuous humming sound" , "Remote controlled aircraft" , "Male bee - monotonous hum" .)