Sausage returned as mail redirected (6)
I believe the answer is:
salami
'sausage' is the definition.
(salami is a kind of sausage)
'returned as mail redirected' is the wordplay.
'returned' says the letters should be written in reverse.
'redirected' is an anagram indicator.
'as' reversed gives 'sa'.
'mail' anagrammed gives 'lami'.
'sa'+'lami'='SALAMI'
(Other definitions for salami that I've seen before include "Highly-spiced sausage" , "Highly spiced sausage" , "Food" , "Sausage served sliced" , "Cured meat" .)