Last word about sound time for reparation (9)
I believe the answer is:
atonement
'reparation' is the definition.
(thesaurus)
'last word about sound time' is the wordplay.
'last word' becomes 'amen' (I've seen this before).
'about' is an insertion indicator.
'sound' becomes 'tone' (tone is a kind of sound**).
'time' becomes 't'.
'amen' going around 'tone' is 'atonemen'.
'atonemen'+'t'='ATONEMENT'
'for' is the link.
(Other definitions for atonement that I've seen before include "reparations?" , "Expiation of sin, penance" , "Making amends" , "Making good" , "Compensation for a wrong" .)