I am sadly returning a sausage (6)
I believe the answer is:
salami
'a sausage' is the definition.
(salami is a kind of sausage)
'i am sadly returning' is the wordplay.
'i am' becomes 'im'.
'sadly' becomes 'alas' (I've seen this before).
'returning' is a reversal indicator.
'im'+'alas'='imalas'
'imalas' reversed gives 'SALAMI'.
(Other definitions for salami that I've seen before include "meat product" , "Highly spiced sausage" , "Highly seasoned fatty sausage" , "Savoury snack" , "Banger" .)