Servant had a mind to change (8)
I believe the answer is:
handmaid
'servant' is the definition.
(synonyms)
'had a mind to change' is the wordplay.
'to change' indicates an anagram.
'had'+'a'+'mind'='hadamind'
'hadamind' with letters rearranged gives 'HANDMAID'.
(Other definitions for handmaid that I've seen before include "Female servant" , "Female attendant" , "servant - with 2d" .)