Cathedral cleric (5)
I believe the answer is:
canon
<span class="explanation-format__ClueExplanation">'<span class="explanation-format__original">cathedral cleric</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 canon that I've seen before include "Such literary works are genuine" , "Principle; list of recognised works" , "Body of generally established principles for a given context" , "Collection of writing" , "Ecclesiastical rule" .)