Melody from a guitar I absolutely loved (4)
I believe the answer is:
aria
'melody' is the definition.
(I've seen this in another clue)
'from a guitar i absolutely loved' is the wordplay.
'from' indicates the answer is hidden within the clue.
'ARIA' is hidden within 'guitar i absolutely loved'.
(Other definitions for aria that I've seen before include "Operatic vocal" , "Imitative art work" , "Song such as "Your Tiny Hand is Frozen"" , "Opera solo" , "Vocal solo in a cantata etc" .)