Temporary substitutes (6)
I believe the answer is:
locums
<span class="explanation-format__ClueExplanation">'<span class="explanation-format__original">temporary substitutes</span>' is the definition.<br/ ><span class="explanation-format__explanation">(I've seen this before)</span><br/ ><br/ >This is all the clue.<br/ ></span>
(Other definitions for locums that I've seen before include "Stand-in doctors" , "Temporary duty doctors" , "Delegates" , "Temporary substitute doctors" , "Temporary substitutes, for doctors perhaps" .)