The Collaborative International Dictionary of English v.0.48:

Cargo \Car"go\, n.; pl. Cargoes. [Sp. cargo, carga, burden,
   load, from cargar to load, from cargar to load, charge, See
   Charge.]
   The lading or freight of a ship or other vessel; the goods,
   merchandise, or whatever is conveyed in a vessel or boat;
   load; freight.
   [1913 Webster]

         Cargoes of food or clothing.             --E. Everett.
   [1913 Webster]

   Note: The term cargo, in law, is usually applied to goods
         only, and not to live animals or persons. --Burill.
         [1913 Webster]

WordNet (r) 3.0 (2006):

cargo
    n 1: goods carried by a large vehicle [syn: cargo, lading,
         freight, load, loading, payload, shipment,
         consignment]