A number in West Side Story save its opening song (4)
I believe the answer is:
aria
'song' is the definition.
(piece of music in an opera)
'a number in west side story save its opening' is the wordplay.
I cannot quite see how this works, but
'a' is present in the answer.
'number' could be 'i' (I is an example) and 'i' is located in the answer.
'side' could be 'r' (abbreviation for right) and 'r' is located in the answer.
A single letter 'a' remains which might be clued in a way I don't understand.
This may be the basis of the clue (or it may be nonsense).
Can you help me to learn more?
(Other definitions for aria that I've seen before include "Operatic number" , "Musical performance" , "complex song" , "Operatic air" , "Imitative art work" .)