Scorn when judgement sees Catholic becoming rector (8)
I believe the answer is:
derision
'scorn' is the definition.
(thesaurus)
I cannot understand how the rest of the clue works.
Can you help me to learn more?
(Other definitions for derision that I've seen before include "'Ridicule, contempt (8)'" , "Mockery, ridicule" , "Contemptuous ridicule" , "Ironside (anag) - mockery" , "Contemptuous mockery" .)