Former leader, second-class, getting money from Iran returned (5)
I believe the answer is:
blair
'former leader' is the definition.
(I've seen this before)
'second-class getting money from iran returned' is the wordplay.
'second class' becomes 'b'.
'getting' says to put letters next to each other.
'money from iran' becomes 'rial' (I am not sure about this - if you are sure you should give a lot more credence to this answer).
'returned' shows that the letters should be reversed in order.
'rial' backwards is 'lair'.
'b'+'lair'='BLAIR'
Can you help me to learn more?
(Other definitions for blair that I've seen before include "Labour leader from 1994" , "He followed Smith as party leader" , "Was this prime minister a Libra?" , "George Orwell's actual family name" , "A political leader" .)