Road surfacing (7)
I believe the answer is:
asphalt
'road surfacing' is the definition.
(I've seen this before)
This is all the clue.
(Other definitions for asphalt that I've seen before include "Material for covering roads" , "Bituminous substance used for roofs and roads" , "Dark natural pitch" , "Mixture of tar and gravel used in road surfaces" , "that's found on the way" .)