Posed (3)
I believe the answer is:
sat
<span class="explanation-format__ClueExplanation">'<span class="explanation-format__original">posed</span>' is the definition.<br/ ><span class="explanation-format__explanation">(posed or sat for an artist)</span><br/ ><br/ >This is the entire clue.<br/ ></span>
(Other definitions for sat that I've seen before include "Took (examination)" , "Relaxed" , "Was couch potato" , "Was in session" , "part of the weekend" .)