Doctor's stand-in (5)
I believe the answer is:
locum
<span class="explanation-format__ClueExplanation">'<span class="explanation-format__original">doctor's stand-in</span>' is the definition.<br/ ><span class="explanation-format__explanation">(I've seen this before)</span><br/ ><br/ >This is the entire clue.<br/ ></span>
(Other definitions for locum that I've seen before include "Stand-in, for a doctor say" , "Temporary replacement doctor" , "Person filling in" , "Physician's stand-in" , "Temporary deputy for doctor" .)