That woman's call to back a liberal dissident (9)
I believe the answer is:
heretical
'dissident' is the definition.
(synonyms)
'that woman's call to back a liberal' is the wordplay.
'that woman's' becomes 'her' (I've seen this before).
'call' becomes 'cite' (citing is a kind of calling).
'to back' is a reversal indicator.
'liberal' becomes 'l' (abbreviation).
'cite' written backwards gives 'etic'.
'her'+'etic'+'a'+'l'='HERETICAL'
(Other definitions for heretical that I've seen before include "about dissident" , "Dissenting" , "At odds with orthodox religious beliefs" , "Contrary to popular belief" , "preaching falsely" .)