Obstinately resistant to change (3-4)
I believe the answer is:
die-hard
'obstinately resistant to change' is the definition.
(I've seen this before)
This is all the clue.
(Other definitions for die-hard that I've seen before include "Backer of a losing cause" , "Obstinate or dauntless person" , "Person who resists change" , "Ultra-conservative" , "Reactionary (supporter)" .)