Warranter

n.	1.	One who warrants, gives authority, or legally empowers.
	2.	(Law) One who assures, or covenants to assure; one who contracts to secure another in a right, or to make good any defect of title or quality; one who gives a warranty; a guarantor; as, the warranter of a horse.

Noun

1.

warranter - one who provides a warrant or guarantee to another Synonyms: guarantor, warrantor, surety

guarantee, guarantor, patron, sponsor, supporter, surety, warrant, warrantor