Freeway exit (4)
I believe the answer is:
ramp
'freeway exit' is the definition.
(I've seen this in another clue)
This is all the clue.
(Other definitions for ramp that I've seen before include "Inclined surface - swindle" , "cheat" , "Change of level in road" , "motorway access road" , "Sloping surface; swindle" .)