Extract from Hungarian melody (4)
I believe the answer is:
aria
'melody' is the definition.
(I've seen this in another clue)
'extract from hungarian' is the wordplay.
'extract from' indicates a hidden word (some letters extracted from the clue).
'ARIA' is hidden in the letters of 'hungarian'.
(Other definitions for aria that I've seen before include "Song, one from 'West Side Story' needing no introduction" , "selection of opera" , "Opera solo" , "Repeated strain" , "Operatic number" .)