Musical postscript (4)
I believe the answer is:
coda
'musical postscript' is the definition.
(I've seen this in another clue)
This is the entire clue.
(Other definitions for coda that I've seen before include "End piece written for a musical work" , "Closing bars (mus.)" , "End piece written for a piece of music" , "Closing stage" , "Word that modifies" .)