It holds the pieces returned (5)
I believe the answer is:
strap
'it holds the' is the definition.
The definition suggests a singular noun which matches the answer.
'pieces returned' is the wordplay.
'pieces' becomes 'parts' ('part' can be a synonym of 'piece').
'returned' is a reversal indicator.
'parts' in reverse letter order is 'STRAP'.
Can you help me to learn more?
(Other definitions for strap that I've seen before include "Beat; securing band" , "loopy band" , "Elongated leather strip" , "Secure" , "Leather fastening" .)