Definition of Expromissor
In the civil law, a person who assumes the debt of another, and becomes solely liable for it, by a stipulation with the creditor. He differs from a surety, inasmuch asthis contract is one of novation, while a surety is jointly liable with his principal.
That's the definition of Expromissor in Black's Law Dictionary 6th Edition. Courtesy of Cekhukum.com.
