Scoundrel, for one, returned to scrounge (5)
I believe the answer is:
cadge
'to scrounge' is the definition.
(synonyms)
'scoundrel for one returned' is the wordplay.
'scoundrel' becomes 'cad' (cad is a kind of scoundrel).
'for one' becomes 'eg' (both can mean 'for example').
'returned' is a reversal indicator.
'eg' in reverse letter order is 'ge'.
'cad'+'ge'='CADGE'
(Other definitions for cadge that I've seen before include "Scrounge, sponge" , "freeload" , "Get by begging" , "Scrouge, ask for" , "Sponge (eg money)" .)