The term 'SECURE, AS A VESSEL' can be summarized as the act of mooring a vessel. Mooring is the process of securing a boat to a dock or other structure in order to keep it from drifting away. It is usually done by tying the vessel to a mooring buoy, pier, or other structure using ropes or chains. Mooring is an important safety measure for vessels, as it prevents them from being swept away by strong currents or winds.