lathe user (6)
I believe the answer is:
turner
'lathe user' is the definition.
(I've seen this before)
This is the entire clue.
(Other definitions for turner that I've seen before include "revolutionary type?" , "Lathe operator and English landscape painter" , "He painted Rain, Steam and Speed - The Great Western Railway" , "Popular English artist" , "Woodworker and English landscape painter" .)