One offers prayers to monarchical bust (5,8)

I believe the answer is:

roman catholic

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'one offers prayers to monarchical bust' is the definition.
I can't tell whether this definition defines the answer.

'to monarchical bust' is the wordplay.
'bust' indicates an anagram.
'to'+'monarchical'='tomonarchical'
'tomonarchical' anagrammed gives 'ROMAN CATHOLIC'.

Can you help me to learn more?

(Other definitions for roman catholic that I've seen before include "RC in full" , "Its head is the Pope" , "Church member" , "Religious believer" .)

I've seen this clue in The Telegraph.

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