In retirement, dined on fine cheese (4)
I believe the answer is:
feta
'cheese' is the definition.
(I've seen this before)
'in retirement dined on fine' is the wordplay.
'in retirement' shows that the letters should be reversed in order (retire can mean to go back or backwards).
'dined on' becomes 'ate' (I've seen this in another clue).
'fine' becomes 'f' (abbreviation).
'ate'+'f'='atef'
'atef' backwards is 'FETA'.
(Other definitions for feta that I've seen before include "10 down cheese" , "Greek dairy product" , "Salty Greek cheese" , "Type of cheese" , "Soft Greek cheese" .)