BONDSMAN, n.
A fool who, having property of his own, undertakes to become responsible for that entrusted to another to a third.
Philippe of Orleans wishing to appoint one of his favorites, a dissolute nobleman, to a high office, asked him what security he would be able to give. "I need no bondsmen," he replied, "for I can give you my word of honor." "And pray what may be the value of that?" inquired the amused Regent. "Monsieur, it is worth its weight in gold."
--Ambrose Bierce - The Devil's Dictionary