'rental' originates from the English base 'rent' plus the suffix '-al', where 'rent' originally meant 'a payment' (income).

'rent' entered Middle English from Old French 'rente' (meaning 'payment, income'), which itself came via Medieval Latin (e.g. 'renta') from earlier Latin roots related to giving or return.

Initially it referred primarily to a payment or income; over time English developed 'rental' to mean both the payment and the item/service made available for temporary use.