Painter's plaster (5)
I believe the answer is:
gesso
'painter's plaster' is the definition.
(I've seen this in another clue)
This is the entire clue.
(Other definitions for gesso that I've seen before include "Plaster of Paris" , "smeared on for starters by artists" , "Type of plaster" , "Could get you plastered" , "Artist's plaster" .)