I unusually retain resistance to change (7)

I believe the answer is:

inertia

'resistance to change' is the definition.
(I've seen this before)

'i unusually retain' is the wordplay.
'unusually' indicates anagramming the letters.
'retain' anagrammed gives 'nertia'.
'i'+'nertia'='INERTIA'

(Other definitions for inertia that I've seen before include "Lack of movement" , "Torpor" , "Passivity" , "Stagnating state" , "Slowness to act, lack of strength" .)

I've seen this clue in The Guardian.

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