Song from Callas, perhaps needing no introduction (4)
I believe the answer is:
aria
'song' is the definition.
(aria is a kind of song)
'callas perhaps needing no introduction' is the wordplay.
'callas perhaps' becomes 'maria' (singer Maria Callas).
'needing no introduction' means to remove the first letter.
'maria' with its initial letter taken away is 'ARIA'.
'from' acts as a link.
(Other definitions for aria that I've seen before include "Puccini item" , "Imitative art work" , "Type of song" , "Opera solo" , "Operatic tune" .)