Windbreaker fabric (5)
I believe the answer is:
nylon
'windbreaker fabric' is the definition.
(I've seen this in another clue)
This is all the clue.
(Other definitions for nylon that I've seen before include "Tights material" , "Stocking; polymer" , "Fibre of polymeric amides" , "Man-made fabric" , "Synthetic cloth" .)