Artist’s model (6)
'artist's model' is the definition.
(I've seen this before)
This is all the clue.
(Other definitions for sitter that I've seen before include "Artist's model - an easy catch" , "eyed by a drawer?" , "One posing for artist" , "broody type" , "Person posing for a portrait" .)
'artist's model?' is the definition.
(artist's model is a kind of poser)
This is all the clue.
(Other definitions for poser that I've seen before include "Problem set by the model" , "Spore raises a difficult question" , "A puzzle made of ropes" , "Problem to be solved" , "Question; one trying to impress" .)