Teacher returned single meatball (7)
I believe the answer is:
rissole
'meatball' is the definition.
The answer and definition can be both things that one consumes for nourishment as well as being singular nouns.
Maybe there's an association between them I don't understand?
'teacher returned single' is the wordplay.
'teacher' becomes 'sir' (way of addressing a male teacher).
'returned' shows that the letters should be reversed in order.
'single' becomes 'sole' (similar in meaning).
'sir' written backwards gives 'ris'.
'ris'+'sole'='RISSOLE'
Can you help me to learn more?
(Other definitions for rissole that I've seen before include "Croquette" , "Meatball fried in crumbs" , "Small cake of deep-fried minced meat" , "faggot" , "Minced meat or fish deep fried in egg and breadcrumbs" .)