'authorize' originates from Late Latin, specifically the word 'authorizare', ultimately from Latin 'auctor' meaning 'originator, author'.

'authorize' changed from Late Latin 'authorizare' to Old French 'autoriser' and entered Middle English (e.g. 'authorisen'), eventually becoming the modern English word 'authorize'.

Initially it meant 'to make or appoint an author/creator or to confer authority', but over time it evolved into the current common meaning 'to give official permission or legal power'.