Clerical gathering admitted to heresy, no doubt (5)
I believe the answer is:
'clerical gathering' is the definition.
(I've seen this in another clue)
'admitted to heresy no doubt' is the wordplay.
'SYNOD' is hidden within the letters.
But, I'm unsure how this is indicated.
Can you help me to learn more?
(Other definitions for synod that I've seen before include "Ecumenical council", "cloth gathered here", "Ecclesiastic council", "Clerical assembly", "Council of bishops".)