On the fourth of July, he could have partnered Cleopatra (5)
I believe the answer is:
anton
'the fourth of july he could have partnered cleopatra' is the definition.
The definition suggests a singular noun which matches the answer.
'on' is the wordplay.
I cannot quite see how this works, but
'on' is found in the answer.
The remaining letters 'ant' is a valid word which might be clued in a way I don't see.
This may be the basis of clue (or it may be nonsense).
Can you help me to learn more?
(Other definitions for anton that I've seen before include "..... Chekov" , "Boy" , "-- Bruckner, composer" , "-- Chekhov, Russian dramatist" , "Chekhov, say" .)