Relax, trainee, and stand (5)
I believe the answer is:
easel
'stand' is the definition.
(stand for an artist's canvas)
'relax trainee' is the wordplay.
'relax' becomes 'ease' (I've seen this in another clue).
'trainee' becomes 'l'.
'ease'+'l'='EASEL'
'and' is the link.
(Other definitions for easel that I've seen before include "Supporter for the artist" , "Painter's tripod" , "supporter of board, perhaps" , "board support" , "Artist's support frame" .)