Synonyms for Cargo boat:

n.

•boat (noun)
canoe, motorboat, galley, ferry, sailboat, aircraft carrier, longboat, barge, steamboat, ship, scull, battleship, merchantman, paddle boat, houseboat, frigate, boat, icebreaker, hulk, hydrofoil, pontoon, rowboat, cruiser, submarine, raft, schooner, trawler, watercraft, bark, vessel, tugboat, dugout, scow, cabin cruiser, kayak, catamaran, destroyer, cutter, Bateau, ocean liner, fishing boat, speedboat, dory, freighter, yacht, liner, gondola, tanker, sampan, dinghy, skiff, gunboat, lifeboat.