Ecclesiastical assembly (5)
I believe the answer is:
synod
<span class="explanation-format__ClueExplanation">'<span class="explanation-format__original">ecclesiastical assembly</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 synod that I've seen before include "council meeting" , "Forum for discussing" , "Church council" , "Ecclesiastical gathering" , "group of clergymen" .)