Money fool returned (3)
I believe the answer is:
tin
'money' is the definition.
(old-fashioned slang term for money)
'fool returned' is the wordplay.
'fool' becomes 'nit' (both can mean a stupid person).
'returned' is a reversal indicator.
'nit' back-to-front is 'TIN'.
(Other definitions for tin that I've seen before include "Kind of metal often used as food container" , "roofing material" , "loaf of bread" , "Cornish metal?" , "Canister" .)