Opera song from Farrar I adored (4)
I believe the answer is:
aria
'opera song' is the definition.
(type of song in an opera)
'from farrar i adored' is the wordplay.
'from' says the answer is hidden in the clue.
'ARIA' is hidden within 'farrar i adored'.
(Other definitions for aria that I've seen before include "Puccini item" , "Song, one from 'West Side Story' needing no introduction" , "Song from an opera (4)" , "selection of opera" , "Piece of music" .)