One supportive of an artist's views? (5)
I believe the answer is:
easel
'one' is the definition.
Although both the answer and definition are singular nouns, I can't see how they can define each other.
I can't explain the remainder of the clue.
Can you help me to learn more?
(Other definitions for easel that I've seen before include "artistic aid" , "Stand in a studio" , "Support for artist's canvas" , "Van Gogh's stand?" , "Tripod supporting a canvas" .)