Covered by Eduardo De Filippo, in retrospect, in biography (4)
I believe the answer is:
life
'biography' is the definition.
(I've seen this before)
'covered by eduardo de filippo in retrospect' is the wordplay.
'covered by' says the answer is hidden in the clue.
'in retrospect' shows that the letters should be reversed in order.
'efil' is hidden in the letters of 'eduardo de filippo'.
'efil' reversed gives 'LIFE'.
'in' acts as a link.
(Other definitions for life that I've seen before include "Animation" , "Existence - biography" , "Maximum stretch?" , "Vitality, vigour" , "and 12 Down: Biology, medicine, etc" .)