'immobilize' originates from French, specifically the word 'immobiliser', where 'in-' meant 'not' and 'mobilis' meant 'movable'.

'immobilize' changed from Late Latin and Old French forms (Late Latin 'immobilis' / Old French 'immobiliser') and eventually became the modern English verb 'immobilize' through adoption and the suffix '-ize'.

Initially it meant 'not movable' (as an adjective); over time it evolved into the verb meaning 'to make not movable' or 'to prevent movement or operation'.