What is the depth of water needed for a vessel to float called?

The depth of water needed for a vessel to float is referred to as the draft. The draft is the vertical distance between the waterline and the lowest point of the vessel's hull, which is usually measured at the keel. This measurement is crucial because it determines how much water a vessel needs to avoid running aground. A vessel with a deeper draft requires deeper water, while one with a shallower draft can navigate in shallower waters. Understanding draft is essential for safe navigation and for planning routes in various water depths. The other terms mentioned have different meanings: the keel is a structural element that runs along the bottom of the hull, displacement refers to the weight of water displaced by the vessel which correlates to its buoyancy, and buoyancy describes the upward force that allows the vessel to float.