[Fr. Frank]

In my mind, displacement should be the gross weight.
Are the terms different on the water
Brandon

I don't know how anything else is weighed. The USCG lists the net weight of a vessel as the weight of the volume of water the vessel displaces as loaded. It is mathematically the same as the vessel's displacement. But as water density can vary, the net weight can change, whereas the calculated displacement remains the same. Displacement is always calculated against fresh water at 59* Fahrenheit. (I don't know why it's calculated that way, but it's the same temperature used as a base when calculating "density altitude" in flying.

At any rate, the net weight of a vessel is the weight of the volume of water it displaces at current loading at rest in current waters. Manufacturers who use net weight for statistical purposes assume maximum loading in fresh water at 59*.

Just make things confusing, the volume of water displaced must actually weigh LESS than the actual weight of the vessel. The difference in weight is called "buoyancy"

Manufacturers generally calculate a vessel's "dry weight". This is the weight of the hull and structural fixtures when dry. It does NOT include the weight of a power-plant, fuel, cushions, seats (unless molded as part of the liner or cap), etcetera, or any optional equipment.