What does the term "draft" refer to in the context of a vessel?

The term "draft" refers specifically to the distance from the waterline down to the bottom of the hull, which is a critical measurement for vessels. This measurement is essential for various reasons, including ensuring sufficient clearance between the vessel's keel and the underwater bottom to avoid running aground, as well as maintaining stability and controlling the ship's buoyancy.

Understanding draft is vital for navigation, particularly in shallow or restricted channels where depth is a concern. It also plays a role in load calculations since a vessel's draft increases as it takes on more cargo. This increase in draft must be managed carefully to ensure compliance with safety and regulatory requirements.

The other options pertain to different aspects of a vessel's dimensions or capabilities. The total length of the vessel refers to its overall size, the height of the vessel above the waterline indicates its freeboard, and the load capacity relates to how much cargo or weight the vessel can safely carry. Each of these measurements is important in its own context but does not define what "draft" means in the maritime field.