Send me right back with it (5)
I believe the answer is:
remit
'send' is the definition.
(thesaurus)
'me right back with it' is the wordplay.
'right' becomes 'r' (common abbreviation).
'back' says the letters should be written backwards.
'with' means one lot of letters go next to another.
'me'+'r'='mer'
'mer' reversed gives 'rem'.
'rem'+'it'='REMIT'
(Other definitions for remit that I've seen before include "Abate; send (money)" , "Transfer - area of authority" , "Send (money) by post" , "Scope of prescribed job" , "Defer" .)