A clue to it is choral and literary work (10,5)
I believe the answer is:
historical novel
'literary work' is the definition.
'a clue to it is choral and' is the wordplay.
I cannot really understand how this works, but
'a' is within the answer.
'to' is within the answer.
'it' could be 'e' ('e' can mean 'electronic' which is similar to 'IT') and 'e' is found within the answer.
'is' is present in the answer.
'and' could be 'n' (common abbreviation for 'and') and 'n' is present in the answer.
This may be the basis of clue (or it may be nonsense).
(Other definitions for historical novel that I've seen before include "work of literature" , "work of fiction" .)