Backsplash piece (4)
I believe the answer is:
tile
'backsplash piece' is the definition.
(I've seen this in another clue)
This is the entire clue.
(Other definitions for tile that I've seen before include "Ceramic slab for roofs, walls, floors etc" , "Roof slabs" , "Flat, thin slab to cover surface" , "Scrabble piece" , "9 for the roof?" .)