Clergyman with idiot in church split (8)
I believe the answer is:
crevasse
'split' is the definition.
(thesaurus)
'clergyman with idiot in church' is the wordplay.
'clergyman with' becomes 'rev' (I can't explain this - if you can you should give a lot more credence to this answer).
'idiot' becomes 'ass' (I've seen this before).
'in' indicates putting letters inside.
'church' becomes 'ce' (abbreviation for Church of England).
'rev'+'ass'='revass'
'revass' going inside 'ce' is 'CREVASSE'.
Can you help me to learn more?
(Other definitions for crevasse that I've seen before include "climbing hazard in glacier" , "Deep glacial crack" , "opening" , "big split" , "gap" .)