A curve in the road (6)
I believe the answer is:
camber
'a curve' is the definition.
(I have seen 'Curve of road ' mean 'camber' so perhaps 'curve' could also mean 'camber')
'road' is the wordplay.
I cannot quite see how this works, but
'road' could be 'm' and 'm' is found within the answer.
The remaining letters 'caber' is a valid word which might be clued in a way I don't understand.
This may be the basis of the clue (or it may be nonsense).
'in the' acts as a link.
Can you help me to learn more?
(Other definitions for camber that I've seen before include "bend in road" , "Convex shape of road surface" , "Road surface curvature" , "may appear on road" , "Slight convexity, like the surface of a road" .)