Staff do right to return (3)
I believe the answer is:
rod
'staff' is the definition.
(thesaurus)
'do right to return' is the wordplay.
'right' becomes 'r' (common abbreviation).
'to return' shows that the letters should be reversed in order.
'do'+'r'='dor'
'dor' backwards is 'ROD'.
(Other definitions for rod that I've seen before include "Wand - fishing stick" , "Little boy" , "Fishing pole" , "Stick - measure" , "The fly fisherman's stick" .)