Queen of Carthage swindled by love (4)
I believe the answer is:
dido
'queen of carthage' is the definition.
(I've seen this before)
'swindled by love' is the wordplay.
'swindled' becomes 'did' (I've seen this before).
'by' means one lot of letters go next to another.
'love' becomes 'o' (love means zero in tennis).
'did'+'o'='DIDO'
(Other definitions for dido that I've seen before include "Carthaginian queen linked to Aeneas" , "Character in Purcell opera" , "Former queen of Carthage" , "Lover of Aeneas" , "---- and Aeneas, opera by Purcell" .)