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' says the answer is hidden in the clue.
'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" .)