Lack of movement (8)
I believe the answer is:
inaction
'lack of movement' is the definition.
(I've seen this before)
This is all the clue.
(Other definitions for inaction that I've seen before include "Dormancy" , "Idleness - fighting" , "Inertia" , "Immobility" , "Lethargy -- not in CIA (anag)" .)