Scoundrel, say, turning bum (5)
I believe the answer is:
cadge
'bum' is the definition.
(I've seen this before)
'scoundrel say turning' is the wordplay.
'scoundrel' becomes 'cad' (cad is a kind of scoundrel).
'say' becomes 'eg'.
'turning' says the letters should be written in reverse.
'eg' reversed gives 'ge'.
'cad'+'ge'='CADGE'
(Other definitions for cadge that I've seen before include "Caged (anag.)" , "Sponge (money, etc)" , "Scrouge, ask for" , "Scrounge (money, etc)" , "Get by begging" .)