Disinclination to move (7)
I believe the answer is:
inertia
'disinclination to move' is the definition.
(I've seen this before)
This is the entire clue.
(Other definitions for inertia that I've seen before include "Listlessness" , "Tendency to inaction" , "Tendency to inactivity" , "Disinclination to respond" , "I retain (anag) - the tendency to retain same speed and direction" .)