Painter's surface (6)
I believe the answer is:
canvas
'painter's surface' is the definition.
(I've seen this in another clue)
This is all the clue.
(Other definitions for canvas that I've seen before include "Cloth for painting etc" , "Sailcloth" , "Heavy fabric used by politicians?" , "An artist paints on it" , "A painter paints on it" .)