Very quiet concession (3)
I believe the answer is:
sop
'concession' is the definition.
(I know that sop is a type of concession)
'very quiet' is the wordplay.
'very' becomes 'so' (both can mean 'extremely').
'quiet' becomes 'p' (music symbol for 'piano', ie soft or quiet).
'so'+'p'='SOP'
(Other definitions for sop that I've seen before include "Piece of bread dipped in liquid, or a concession" , "usual way of doing things, initially" , "Bread dipped in gravy" , "A bribe or appeasement" , "Appeasing bribe" .)