Philosopher Diderot
I believe the answer is:
denis
<span class="explanation-format__ClueExplanation">'<span class="explanation-format__original">philosopher diderot</span>' is the definition.<br/ ><span class="explanation-format__explanation">(I've seen this in another clue)</span><br/ ><br/ >This is all the clue.<br/ ></span>
(Other definitions for denis that I've seen before include "- Healey, former Chancellor of the Exchequer" , "Patron saint of France" , "St -, first Paris bishop" .)