Give firm backing to worship that's mythical (6)
I believe the answer is:
occult
'mythical' is the definition.
Both the answer and definition are adjectives. Perhaps you can see a link between them that I don't see?
'give firm backing to worship' is the wordplay.
'give' says to put letters next to each other.
'firm' becomes 'co' (a firm is a company).
'backing' says the letters should be written backwards.
'to worship' becomes 'cult' (I've seen this in another clue).
'co' backwards is 'oc'.
'oc'+'cult' is 'OCCULT'.
'that's' is the link.
Can you help me to learn more?
(Other definitions for occult that I've seen before include "Magical; secret" , "Hidden - paranormal" , "Magical; hide from view (astron.)" , "Involving magical powers" , "Mystical, involving the supernatural" .)