Definitions for "Moon pool"
Keywords:  hull, drill, drillship, undersea, ark
a walled round hole or well in the hull of a drill ship (usually in the center) through which the drilling assembly and other assemblies pass while a well is being drilled, completed, or abandoned from the drill ship.
a vertical hole clear through the vessel (rectangular in the Ark), from the main deck down through the bottom (most commonly found in modern drill rigs)
a large opening through the deck and bottom plating of a ship for special operational requirement, e.g. drilling