loaner

loaner [loh-ner] Word Origin noun

1. a person or thing that loans.
2. something, as an automobile or appliance, that is lent especially to replace an item being serviced or repaired.

Origin of loaner First recorded in 1880–85; loan1 + -er1 Word Origin and History for loaner n.

1884, “one who lends,” agent noun from loan (v.). Meaning “a thing loaned” especially in place of one being repaired, is from 1926.