Fruit a must when suffering rejection (7)
I believe the answer is:
satsuma
'fruit' is the definition.
(I know that satsuma is a type of fruit)
'a must when suffering rejection' is the wordplay.
'when suffering' becomes 'as' (I can't explain this - if you can you should believe this answer much more).
'rejection' says the letters should be written backwards (to reject is to send back).
'a'+'must'+'as'='amustas'
'amustas' in reverse letter order is 'SATSUMA'.
Can you help me to learn more?
(Other definitions for satsuma that I've seen before include "that's segmented" , "Type of tangerine" , "Japanese province and small orange" , "Orange, district and style of Japanese pottery" , "A small citrus fruit" .)