Disinclination to move it back through in time (7)
I believe the answer is:
inertia
'disinclination to move' is the definition.
(I've seen this before)
'it back through in time' is the wordplay.
'back' says the letters should be written backwards.
'through' is an insertion indicator (I've seen this in other clues).
'time' becomes 'era' (era is a kind of time).
'it' reversed gives 'ti'.
'in'+'era'='inera'
'ti' put within 'inera' is 'INERTIA'.
(Other definitions for inertia that I've seen before include "Disinclination to respond" , "Disinclination to change" , "Stagnating state" , "Motion (if any) when no external force is applied" , "'Sluggishness, indolence (7)'" .)