Supercargo, a term in maritime law (adapted from the Span. sobrecargo, one over or in charge of a cargo) for a person employed on board a vessel by the owners of the cargo to manage their trade, sell the merchandise at the ports to which the vessel is sailing, and buy and receive goods for shipment homewards. He has control of the cargo unless expressly or impliedly limited by his contract or agreement. He differs from a factor, who has a fixed place of residence at a port or trading place, by sailing from port to port with the vessel to which he is attached.