House's exterior finish (6)
I believe the answer is:
stucco
'house's exterior finish' is the definition.
(I've seen this in another clue)
This is the entire clue.
(Other definitions for stucco that I've seen before include "Cement or plaster used for coating walls" , "A wall-coating plaster" , "Decorative wall coating" , "Outer layer" , "Coating material" .)