Wife abandons sly individual to give support to artist (5)
I believe the answer is:
Here is my best explanation:
'wife' 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 rest of the clue.
(Other definitions for easel that I've seen before include "Artist's stand for canvas", "Supporter for the artist", "artist's requisite", "A stand for blackboard or artist's canvas", "Framework to hold a canvas", "art supporter", "Board supporter", "stand for creativity", "Artistic support" and "Picture stand".)