Rural parts of motorways? (5)

I believe the answer is:

lanes

I'm a little stuck... Click here to teach me more about this clue!

'parts of motorways?' is the definition.
(I know that roadway is part of expressway)

I don't understand how the remainder of the clue works.

Can you help me to learn more?

(Other definitions for lanes that I've seen before include "Tracks for traffic" , "Narrow tracks or paths" , "Country roads" , "Leans into narrow roads" , "Narrow roads or road divisions" .)

I've seen this clue in the Evening Standard.

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