Resistance to change (7)
I believe the answer is:
inertia
'resistance to change' is the definition.
(I've seen this in another clue)
This is all the clue.
(Other definitions for inertia that I've seen before include "Motion (if any) when no external force is applied" , "Torpor" , "I retain (anag) - the tendency to retain same speed and direction" , "Slowness to move or act" , "Tendency to inaction" .)