Lover of Aeneas accomplished nothing (4)
I believe the answer is:
dido
'lover of aeneas' is the definition.
(I've seen this in another clue)
'accomplished nothing' is the wordplay.
'accomplished' becomes 'did' (to do something is to accomplish it).
'nothing' becomes 'O' (O resembles 0).
'did'+'o'='DIDO'
(Other definitions for dido that I've seen before include "Lover of Aeneas" , "Founding queen of Carthage (did next to nothing!)" , "Antic" , "Queen < singer" , "Tyre lady" .)