in our ancient customs, signified a tenant or feudatory; or person who vowed fidelity and homage to a lord, on account of some land, &c., held of him in fee; also a slave or servant, and especially a domestic of a prince.—Vassallus is said to be quasi inferior socius; as the vassal is inferior to his master, and must serve him; and yet he is in a manner his companion, because each of them is obliged to the other. See FEUDAL System.