"Clair de Lune" composer (7)
I believe the answer is:
debussy
'clair de lune composer' is the definition.
(I've seen this before)
This is the entire clue.
(Other definitions for debussy that I've seen before include "Note-writer" , "Claude -, Fr. composer" , "Clair de Lune composer" , "Claude, impressionist composer" , "Claude -, C. nineteen-twenty French composer" .)