Airboat means a vessel that is typically flat-bottomed and propelled by an aircraft-type propeller powered by an engine.

Auxiliary sail means a vessel with sail as its primary method of propulsion and mechanical propulsion as its secondary method.

Cabin motorboat means a vessel propelled by propulsion machinery and providing enclosed spaces inside its structure.

Certificate of number means the certificate required by 33 CFR 173.21.

Charter fishing means a vessel carrying a passenger(s) for hire who is (are) engaged in recreational fishing.

Commercial fishing means a vessel that commercially engages in the catching, taking, or harvesting of fish which, either in whole or in part, is intended to enter commerce through sale, barter, or trade.

Houseboat means a motorized vessel that is usually non-planing and designed primarily for multi-purpose accommodation spaces with low freeboard and little or no foredeck or cockpit.

Hull identification number or HIN means a number required by 33 CFR 181.23.

Inboard, in the context of an engine, means an engine mounted inside the confines of a vessel which powers a drive shaft that turns a water jet impeller or that runs through the bottom of the hull and is attached to a propeller at the other end.

Inflatable boat means a vessel that uses air-filled flexible fabric for buoyancy.

Open motorboat means a vessel equipped with propulsion machinery and having an open load carrying area that does not have a continuous deck to protect it from the entry of water.

Operate means use, navigate, or employ.

Operator means the person who is in control or in charge of a vessel while it is in operation.

Outboard, in the context of an engine, means an engine with propeller or water jet integrally attached, which is usually mounted at the stern of a vessel.

Owner means a person, other than a secured party, having property rights in or title to a vessel, including persons entitled to use or possess a vessel subject to a security interest in another person, but excluding lessees under a lease not intended as security.

Paddlecraft means a vessel powered only by its occupants, using a single or double bladed paddle as a lever without the aid of a fulcrum provided by oarlocks, thole pins, crutches, or similar arrangements.

Person means an individual, firm, partnership, corporation, company, association, joint-stock association, or governmental entity and includes a trustee, receiver, assignee, or similar representative of any of them.

Personal watercraft means a vessel propelled by a water-jet pump or other machinery as its primary source of motive power and designed to be operated by a person sitting, standing, or kneeling on the vessel, rather than sitting or standing within the vessel's hull.

Pod drive means an engine mounted in front of the transom of a vessel and attached through the bottom of the hull to a steerable propulsion unit.

Pontoon boat means a vessel with a broad, flat deck that is affixed on top of closed cylinders which are used for buoyancy, the basic design of which is usually implemented with two rows of floats as a catamaran or with three rows of floats as a trimaran.

Reporting authority means a State listed in 33 CFR part 173, Appendix A, as having a numbering system approved by the Coast Guard or the Coast Guard itself when a numbering system has not been approved.

Rowboat means an open vessel manually propelled by oars.

Sail only means a vessel propelled only by sails.

State means a State of the United States, the District of Columbia, American Samoa, Guam, the Commonwealth of the Northern Mariana Islands, Puerto Rico, the U.S. Virgin Islands, and any other territory or possession of the United States.

State of principal operation means the State in whose waters a vessel is or will be operated most during a calendar year.

Sterndrive means an engine, powering a propeller using shifts and gears, mounted in front of the transom of a vessel and attached through the transom to a drive unit that is similar to the lower unit of an outboard, which may also be known as an inboard-outdrive or an inboard-outboard.

Vessel means every description of watercraft or other artificial contrivance used, or capable of being used, as a means of transportation on water.