Number from Marianne (4)
I believe the answer is:
aria
'number' is the definition.
(I have seen 'Operatic number ' mean 'aria' so perhaps 'number' could also mean 'aria')
'from marianne' is the wordplay.
'from' indicates a hidden word.
'ARIA' is hidden in the letters of 'marianne'.
(Other definitions for aria that I've seen before include "Nessun Dorma, for example" , "Operatic air" , "Repeated strain" , "Vocal solo in a cantata etc" , "Operatic song" .)