Glossary of maritime terminology

A vacuum toilet, also called a marine toilet or ship toilet, is used on boats and ships of all types and sizes. Vacuum toilets work by removing the waste from the bowl by suction and then depositing it in a holding tank when the toilet is flushed. Traditional toilets, such as those found in the home, use a combination of water and gravity to transport the waste from the bowl to a collection or treatment tank.

Like regular toilets, vacuum toilets use water to flush although in far smaller quantities - typically around 1.5 liters of water per flush as opposed to the 10 liters used by a non-vacuum toilet.

The valve remote control system (VRC), sometimes also called a remote control valve system (rcVS), on a ship is used to control various pumps such as the bilge pump, fuel transfer pump, fire pump and ballast pump. It directs the flow of the fluids and liquids that work with these pumps - for example fuel oil, ballast water or bilge water. The valves are opened and closed remotely by electric, pneumatic, hydraulic, or electro-hydraulic actuators.

VDR, in shipping terms, is the abbreviation for voyage data recorder and is often referred to as the 'black box' of the ship. It collects and stores data over the course of a vessel’s voyage including the ship's position, the speed and heading and the depth of the water beneath the keel. It also records audio from the ship's bridge.

A Vector Chart, also referred to in maritime terminology, as an Electronic Nautical Chart (ENC), or  Electronic Navigational Chart is a data set that provides ships with information, including real time information. This information can then be displayed on the screen of the vessel's Electronic Chart Display and Information System (ECDIS). It helps navigators determine their position, be aware of any hazards, and plot their route more efficiently and safely.

A vessel is the term given to a large boat or a ship. Merchant mariners working on container ships and tankers, and others in the maritime industry, will usually use the term vessel instead of ship.

A VHF radio is a globally-used system of two way radio transceivers on ships and boats that is used for bidirectional voice communication. In other words, it is a form of two-way radio telephone. Communication may be from ship-to-ship or ship-to-shore - for example a vessel communicating with the harbormaster or port authority.

Victor stands for the letter V in the International Radiotelephony Spelling Alphabet, which is most often referred to as the NATO Phonetic Alphabet or simply the Phonetic Alphabet. This is the most commonly used group of code words used to clearly communicate the letters of the Roman alphabet, particularly over the radio and is essential in helping seafarers give and receive messages, orders and instructions clearly and correctly.

On a ship the viscosity controller, also known as the viscosity regulator, plays a crucial role in ensuring that the fuel oil temperature is right so that the correct viscosity for combustion and atomization can take place. If the temperature of the fuel is increased, its viscosity will be reduced and vice versa. The viscosity controller uses a pre-warming bypass to heat the fuel before the engine is started and consists of a valve that regulates the pressure supply to the engine-driven pumps.

On a ship the viscosity regulator, also known as the viscosity controller in maritime terms, plays a crucial role in ensuring that the fuel oil temperature is right so that the correct viscosity for combustion and atomization can take place.

If the temperature of the fuel is increased, its viscosity will be reduced and vice versa. The viscosity controller uses a pre-warming bypass to heat the fuel before the engine is started and consists of a valve that regulates the pressure supply to the engine-driven pumps.

VLCC stands for Very Large Crude Carrier - an oil, chemical or petroleum tanker that is generally between 200,000 and 500,000 DWT.

VLCS, in freight terms, stands for Very Large Container Ship - a container vessel with the capacity to carry around 8000+ TEU.

VLEC stands for Very Large Ethane Carrier - a class of gas carrier vessels designed to transport ethane that generally has a capacity of between 70,000 and 90,000 CBM.

VLGC stands for Very Large Gas Carrier - a class of vessel designed to transport LPG (Liquified Petroleum Gas) that generally has a capacity of between 70000 and 90000 CBM.

A voyage data recorder (VDR) is often referred to as the 'black box' of the ship. It collects and stores data over the course of a vessel’s voyage including the ship's position, the speed and heading and the depth of the water beneath the keel. It also records audio from the ship's bridge.