Mistakenly copies friend of the bishop (9)
I believe the answer is:
episcopal
'mistakenly copies friend of the bishop' is the definition.
I can't judge whether this defines the answer.
'mistakenly copies friend' is the wordplay.
'mistakenly' indicates an anagram.
'friend' becomes 'pal' (pal can mean a friend).
'copies' with letters rearranged gives 'episco'.
'episco'+'pal'='EPISCOPAL'
Can you help me to learn more?
(Other definitions for episcopal that I've seen before include "Alice's pop? (anag)" , "work of bencher" , "sees can be described thus" , "To do with bishop - maybe Pepsi-Cola" , "Governed by bishops" .)