Dad possibly sent back lots of fruit? (7)
I believe the answer is:
papayas
'lots of fruit?' is the definition.
Although both the answer and definition are plural nouns, I can't see how one could define the other.
'dad possibly sent back' is the wordplay.
'dad' becomes 'papa' (synonyms).
'possibly' becomes 'say' (I can't justify this - if you can you should give a lot more credence to this answer).
'sent back' is a reversal indicator.
'say' backwards is 'yas'.
'papa'+'yas'='PAPAYAS'
Can you help me to learn more?
(Other definitions for papayas that I've seen before include "Large oblong yellow fruits" , "Fruit like melons" .)