Mosaic artist (5)
I believe the answer is:
tiler
'mosaic artist' is the definition.
(I've seen this in another clue)
This is all the clue.
(Other definitions for tiler that I've seen before include "Tradesman who covers roofs or bathroom walls with rectangular materials" , "Workman who fixes glazed rectangles in bathrooms" , "High-level operator" , "Relit for tradesman" , "Craftsman" .)