Prisoner to leave African flower (5)
I believe the answer is:
congo
'african flower' is the definition.
'Congo' can be an answer for 'flower' (Congo is an example). I am not certain of the 'african' bit.
'prisoner to leave' is the wordplay.
'prisoner' becomes 'con' (abbreviation for 'convict').
'to leave' becomes 'go' (to go is to depart or leave).
'con'+'go'='CONGO'
Can you help me to learn more?
(Other definitions for congo that I've seen before include "African river flowing into the South Atlantic" , "Africa's second longest river" , "Second longest river of Africa" , "Wide river" , "African river/republic" .)