The main body of a ship is the hull.
hull
The main body of a ship is called the hull. The hull runs from the main deck of the vessel all the way to the keel, which is at the center of the vessel where both sides of the hull join under the water. The part of the ship that is built above the hull is called the superstructure.
Their main ship was the Mayflower.
main part of a ship
Main engine is used for propulsion of ship.
Ship's freeboard
bridge and main deck
The keelboat was the main ship
bridge and main deck
The Hull is the body of the ship
Usually referring to as the "Poop Deck",it is the main deck on a ship.