'usurer' originates from Old French, specifically the word 'usurier', where 'usure' meant 'interest'.

'usurier' transformed into the Middle English word 'usurer', and eventually became the modern English word 'usurer'.

Initially, it meant 'one who lends money at interest', but over time it evolved into its current meaning of 'a person who lends money at unreasonably high rates of interest'.