- guarantee (n.)
- 1679, perhaps via Sp. garante, from O.Fr. guarantie, pp. of fem. guarantir "to protect," from guarant "warrant," from Frank. *warjand-s, from P.Gmc. *war-, from PIE base *wer- "to cover" (see warrant). For form evolution, see gu-. Originally "person giving something as security," sense of the "pledge" itself (which is properly a guarranty) first recorded 1786. The verb is attested from 1791.