Hard-wearing material (5)
I believe the answer is:
denim
'hard-wearing material' is the definition.
(I've seen this before)
This is the entire clue.
(Other definitions for denim that I've seen before include "Thick cotton cloth" , "Material for casual trousers or jackets" , "Hard-wearing clothing material, twilled cotton" , "Durable material" , "Cloth for jeans, etc" .)