Paving material (6)
I believe the answer is:
tarmac
'paving material' is the definition.
(tarmac is a kind of paving material)
This is all the clue.
(Other definitions for tarmac that I've seen before include "Planes taxi on it" , "something for the road" , "Airport runway(s)" , "Trade name for road surfacing material" , "Surface material of tar and broken stone" .)