Twenty around church registered a hot one (8)
I believe the answer is:
scorcher
'a hot one' is the definition.
Although both the answer and definition are singular nouns, I don't see how they can define each other.
'twenty around church registered' is the wordplay.
'twenty' becomes 'score' (synonyms).
'around' indicates putting letters inside.
'church' becomes 'ch' (common abbreviation).
'registered' becomes 'r' (this might be a standard abbreviation I've not previously seen).
'score' enclosing 'ch' is 'scorche'.
'scorche'+'r'='SCORCHER'
Can you help me to learn more?
(Other definitions for scorcher that I've seen before include "something remarkable" , "Brand, perhaps" , "A boiling hot day" , "heat wave" , "for example, really fine" .)