Misguided members of cult aren't unwilling (9)
I believe the answer is:
reluctant
'unwilling' is the definition.
('reluctant' can be similar in meaning to 'unwilling')
'misguided members of cult aren't' is the wordplay.
'misguided members of' is an anagram indicator (parts or members of the words get rearranged).
'cult'+'arent'='cultarent'
'cultarent' anagrammed gives 'RELUCTANT'.
(Other definitions for reluctant that I've seen before include "Kenneth Grahame's dragon was" , "Unwilling, hesitant" , "Indisposed" , "Not wishing to" , "Unwilling to do something" .)