Brazen scoundrel, on reflection, promises to pay with gold at the start (9)
I believe the answer is:
audacious
'brazen' is the definition.
(synonyms)
'scoundrel on reflection promises to pay with gold at the start' is the wordplay.
'scoundrel' becomes 'cad' (cad is a kind of scoundrel).
'on reflection' shows that the letters should be reversed in order.
'promises to pay' becomes 'IOU's' (promises to pay a debt).
'with gold' becomes 'au' (Au is the chemical symbol for gold. I am not sure about the 'with' bit.).
'at the start' means one lot of letters go next to another.
'cad' backwards is 'dac'.
'dac'+'ious'='dacious'
'dacious' put after 'au' is 'AUDACIOUS'.
Can you help me to learn more?
(Other definitions for audacious that I've seen before include "Bold and daring" , "Bold - impertinent" , "Brazen" , "Recklessly bold" , "Intrepid" .)