Witch is repulsed by Roman cardinal (5)
I believe the answer is:
sibyl
'witch' is the definition.
The definition and answer can be both people as well as being singular nouns.
Perhaps you can see an association between them that I can't see?
'is repulsed by roman cardinal' is the wordplay.
'repulsed' says the letters should be written in reverse.
'roman cardinal' becomes 'l' (similar in meaning. I am not sure about the 'roman' bit.).
'is' backwards is 'si'.
'si'+'by'+'l'='SIBYL'
Can you help me to learn more?
(Other definitions for sibyl that I've seen before include "Woman mouthpiece of a god, uttering prophecies" , "Female seer" , "Female oracle" , "Greek oracle" , "One seeing future" .)