Do well (at) (5)
I believe the answer is:
excel
<span class="explanation-format__ClueExplanation">'<span class="explanation-format__original">do well at</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 excel that I've seen before include "Do brilliantly" , "Be outstanding" , "Predominate in" , "Every one" , "Perform outstandingly well" .)