Enclosed area may be risk with wagon reversing (9)
I believe the answer is:
courtyard
'enclosed area' is the definition.
(I've seen this before)
'risk with wagon reversing' is the wordplay.
'risk with' becomes 'court' (I am not sure about this - if you are sure you should believe this answer much more).
'wagon' becomes 'dray' (dray is a kind of wagon).
'reversing' shows that the letters should be reversed in order.
'dray' reversed gives 'yard'.
'court'+'yard'='COURTYARD'
'may be' is the link.
Can you help me to learn more?
(Other definitions for courtyard that I've seen before include "enclosed area" , "Open-air enclosure attached to a house" , "Enclosure open to the sky attached to a house" , "Quadrangle" , "Dry out car in space enclosed by buildings" .)