Space; opportunity (4)
I believe the answer is:
room
I believe this clue is a double definition.
'space' is the first definition.
(enough space or room to do something)
'opportunity' is the second definition.
(room or space to do something)
(Other definitions for room that I've seen before include "Capacity" , "Space, area" , "Latitude" , "Enclosed part of building" , "Opportunity, scope" .)