Marine terminology is essential for boat owners, mariners and those in the maritime industry. It is important for even the novice to understand and know common maritime terms that are related to their ship or boat. Most of these terms relate to the position of vessels and their direction of movement.
It may seem simple to most people, but for non-mariners it is a foreign language. Many beginners will discover for the first times that there are no left and right on ships and boats, but only port and starboard. When a ship or boat is moving forward, the left side is called port and the right is called starboard.
Get to know these boating words and enjoy your sailing experience. If you don’t, then marine terminologies can be a barrier to communication on boats and ships. It’s especially important when the majority of people on board are experienced, and you are new to sailing.
Common Marine Terminology in Ships & Boats
Marine Terminology Beginning with “A”
Aft is the term used to describe the rear portion of a vessel, whether it’s a plane, boat or ship. Aft in nautical terms is the back of the vessel or the stern. It can be said that aft is what is facing backwards when you are inside the vessel, with your head facing the bow.
Abeam is the nautical term for at right angles with the centerline of a ship’s keel. It means, in simple terms, on the beam of either side of the vessel.
Aloft is the area above the waterline of the boat’s deck. Deck is the term used for the topmost floor of a ship or boat. However, it can also refer to the floor of a boat or ship in general.
Amidship is the middle part of a vessel when viewed longitudinally. It is the part of a ship or boat that lies between the bows and sterns. The bow of a vessel is its front, while the stern represents the back.
Ahead: The term ahead is used to describe the movement of a ship whose bow faces forward in the direction that the movement takes place. It is simply the forward movement made by the boat or ship.
Astern: Astern is the term used to describe the movement of a boat or ship when its bow faces forward, away from the direction in which it is moving. It is simply the reverse movement of a vessel.
Aboard is a maritime term that means an object, person or boat is on a ship, boat or vessel.
Abandon Ship: In an emergency, the captain will use the phrase “abandon ship” to order all crew and personnel to leave the vessel.
Adrift: When a boat, ship, or vessel is floating on the water without its own propulsion system it is considered to be adrift. This term is also used to describe boats and floating bodies that are not tied or secured near ports.
Ahoy is used as a signal to attract attention or to greet another vessel or boat.
The ship’s side that is sheltered or away from the wind.
Alongside is a nautical term that means a vessel, boat, or ship is next to your ship/boat. It is generally used to describe the side of a vessel.
Anchor: An anchor is a device that keeps a ship or boat anchored in place when it’s not being propelled. You can also moor the anchor to the bottom of your ship. They can be permanent or temporary and are usually a heavy metal, with a fluke and a shank.
Anchor buoy: A small floating object with a line attached that shows the actual position of the anchor in the water after it is released.
Abaft – The term is used in order to describe the back or stern of a ship, or to describe a part of a ship or boat. Go abaft, for example, the port bow.
A.B. Able Seaman. He is a senior seaman who has responsibilities like maintenance, sanitation and emergency equipment and life-saving gear on merchant ships.
Accommodation: Upper deck of a ship used for living, cooking and recreation. It is usually located aft, above the upper deck. These ships have two to three decks of crew quarters, and a mast-topped bridge.
Awash: When a ship or boat is too low to the water, the seawater is constantly washing over the surface of the vessel.
Marine Terms Beginning with “B”
Ballast is the counterweight that’s added to a ship, based on the stability curve. This helps stabilize the vessel. In the past, ballast was added to ships as physical weights. Now there are special tanks for this purpose. The ballast tanks are filled with water when the ship releases its cargo. This helps to keep it stable.
Beam: The beam is the greatest width of a boat. It is the measurement for the width of the vessel.
Bow: The bow is the forward-most part of any ship or boat.
Buoys: A buoy is an object that floats and acts as a navigational aid. They can serve multiple purposes, and they can either be anchored or float free.
On a boat, the term berth can refer to two different places. The first is the place the boat is moored. The other is for the sleeping area or cabin of a boat.
Bilge is the lowermost compartment of a ship or boat. Bilge wells, which are usually located in the bilges of ships and boats to store extra water during flooding, are designed to be located there.
Bulkhead is a support structure that divides the ship or two-compartment into different compartments, much like a wall. This transverse structure also supports different decks on boats and ships.
Bowline: This ancient knot is a great way to create a loop in a rope or thread. It is easy to learn and simple. This method has the advantage of being easier to untie regardless of the load applied.
The bridge is the compartment located at the top level of the accommodation block. It is from here that the ship is navigated. The bridge, unlike any other part of a ship, is always manned by a watchkeeping officer. All major decisions made on the bridge are officially the responsibility of the captain and chief officer.
Marine Terms Beginning with “C”
Cleat is a nautical term for small bars, hooks, or metal fittings used on boats to secure a rope or a line. These are useful for securing your boat or tying it to the dock.
Capsize is when a boat or ship rolls over or tilts too far, exposing its keel. Capsize is the term used to describe a ship or boat that has turned upside down. This condition causes most larger boats and ships to break apart. It is also called sinking a ship.
Chain locker: The chain locker is the space in the forward section of the vessel that is used to store the anchor while the vessel is at sea. It’s located exactly under the windlass on large ships and is usually divided by a longitudinal bulkhead.
Catamaran is the marine term for a type of ferryboat with two hulls. Its two parallel hulls are of equal size, which gives it an obvious advantage when it comes to stability. These boats are mainly used for recreational and water sports.
Course: The planned or intended path of the vessel.
Cuddy: This is a type of boat that’s primarily used for fishing. It has a cabin built into the boat. They are small, easy to handle and great for family experiences.
Cabin is a maritime term that refers to a room or compartment on a ship or boat.
Cable: In marine terminology, a rope is referred to as a cable if it is long.
Current: This is the horizontal movement in water caused by many forces, including wind, boat movements, waves and Coriolis effects.
Cockpit is the area on a vessel where the boat is navigated or steered. It is usually located in the middle, but can also be at the stern.
Marine Terminology Beginning with “D”
It is the height or depth of the ship hull, or boat keel, below the level of water. This is a common way to measure the stability of a water vessel.
Dock is a maritime term that means a safe area where ships or boats can moor. Docks are used for loading, unloading and landing ships or boats, as well as repairs.
Dock-line is a rope or line that’s used to attach a ship or boat to a dock, either temporarily or permanently. Dock-line can be used for securing a ship or boat on another vessel or boat.
Deck: The deck is the floor of a ship or boat.
Dead Ahead is a term used in the maritime industry to indicate that you should move forward or go straight ahead.
Dead Astern is the marine term for moving 180 degrees in the opposite direction.
Davit: This small crane is used on large ships and boats to lift, lower and support anchors, lifeboats, and tenders. This crane is not uncommonly used to lift objects onto and off of the supporting vessel.
Deadrise is the angle formed between the hull plane and the horizontal plane on either side of a keel. The deadrise is lowest at the transom and increases as you progress forward along the keel to the bow. Deadrise is usually 20-35 at the bow and 8-18 at the transom for a typical boat.
Displacement is the amount of water that is displaced from a floating object. For a boat or ship, displacement is usually referred to as the ship’s weight. It is usually measured with all of the crew, appliances, and objects on board, as well as full fuel tanks.
Marine Terminology Beginning with “E”
EPIRB is an acronym for Emergency Position Indicating radio Beacon. It sends radio signals to satellites, planes and other nearby vessels once it has been activated. This is similar to an emergency beacon that will alert others of your location.
Enclosed space: Any confined area on a vessel where natural ventilation is not available. It is dangerous for a single person to enter such enclosed spaces on ships. Special permits are needed to work in these areas.
Enclosed waters are any navigation waterways that are too close to or surrounded on all sides by land. Enclosed waters include, for example, the areas around ports and any navigating water line such as canals and channels.
Ensign: This is the flag of the flag state representing the nationality or boat.
The engine room is located on the lowermost deck of the ship, aft. The engine room contains a variety of important machinery including the main engine (alternator), auxiliary engine, shafting, boilers, freshwater generators, air compressors, calorifiers, purifiers, incinerators, pumps, heat-exchangers, workshop equipment, etc.
Marine Terms Beginning with “F”
Forward: To the front or bow.
Freeboard is the exposed part of a ship’s hull. It is simply the distance between the waterline and the main deck of a ship (or the gunwale on a boat).
Flybridge: On some boats, a steering compartment is located on top of a cabin that has additional features such as large space and entertainment equipment. This up-top steering station is known as the flying bridge or flybridge.
Foredeck is the deck that faces forward, near the bow of a ship. It contains critical instruments like windlass and an anchor with chain.
Fastened/Fast is a maritime term used to describe a tie that is secure or tied.
Fender: This is a vital instrument that acts as a bumper to protect your boat’s or ship’s hull. It is used when two ships or boats approach each other to absorb residual forces that could otherwise damage the docking platform or vessel.
Flare: A signaling device used by ships and planes to alert other vessels or planes nearby for help or rescue.
The maximum speed that a boat or ship can go in any situation is called the “flank”. This is not the same as full speed, which is the maximum speed that a vessel can go in normal conditions. In general, flank speeds are reserved for emergencies and not used in other situations.
Fouled: A machine, instrument or device that is jammed, clogged or breaks down due to dirt, is considered fouled.
It is the chimney from which the ship’s exhaust gas or flue gases escape. The main exhaust gases are from the boilers, auxiliary engines and the main engine.
Forecastle: A forecastle is an elevated deck structure that’s forward of the foremast and used to store stores and machinery. It was used to house the crew in the old days, and on many naval vessels.
Marine Terms Beginning with “G”
Give-away: This is a maritime term used to describe a situation in which a boat or ship must change its direction or speed to maintain a safe distance. It is simply a matter of giving her a pass, or staying out of the way.
The kitchen or galley of a ship.
A gangway (temporary stairs) is a narrow passage used by most ships to embark or disembark. You can also refer to it as an opening on the bulwark that is used to embark some ships and boats.
GPS is an acronym for “Global Positioning System”. This satellite-based navigation system allows us to navigate and geolocate anywhere on the planet. It helps keep ships at a safe distance from one another and avoid collisions.
The grounding of a boat or ship occurs when the keel contacts the seabed or the ground. The ship is subjected to an impact force which can cause damage and flooding in the lower compartments.
Gunwales are the top edges of the hulls of ships and boats. It can be considered the uppermost part of a boat’s side.
Grab-Rails : Because a boat moves in a bouncing and pitching motion, there are metal fittings in various places around the boat that allow you to move safely around the vessel while holding them in even the worst weather conditions. Grab-rails are metal fittings that provide safety.
Marine Terms Beginning with “H”
Hull: The outermost part of a ship’s body on which all major structural elements are built. It extends beneath the waterline in order to protect the ship’s internal structure from outside water. The ship’s hull protects and covers everything within the main structure of the ship.
Head: Marine toilets on boats and yachts are commonly referred to as the “head”. Sometimes it is used to describe the forward or top direction.
Hatch is a nautical door or cover used to separate compartments that is water, heat, or weatherproof. Also known as hatch covers.
Helm: A place in a boat that has all the controls for steering and engines located at one location. The steering wheel is another meaning of helm.
Harbor: A harbor, also known as a safe area in the sea, is an area that is protected from weather conditions. It’s used for anchoring, berthing and loading/unloading operations. Both man-made and natural harbors are used by boats and ships.
Hawse Pipe: This is the hole or shaft in the hull of the ship that leads to the anchor. It is the hole in your boat where the anchor is secured.
Headway: Forward motion of a vessel is known as headway.
Helmsman is the person who steers a ship or large boat. The helmsman is responsible for steering the ship or boat.
Marine Terms Beginning with “K”
Keel is the central bottom part of a ship or boat’s hull, on which the entire structure of the vessel is built.
Knot: The knot is used as a symbol for nautical miles. The nautical mile is equal to 1,15 miles or 1,85 miles
Marine Terminology Beginning with “L”
Lanyard: The term “lanyard” is used for the rope used on a boat or ship to lower or lift the sail/flag.
Lazarette is a term used in marine terms to describe the space or storage locker found on the back side of the boat. The storage lockers are used for storing all the necessary equipment and gear required by sailors. Included are boating parts, spare lines and sails, boat hooks, fenders, life-saving gear, and spare lines.
Leeway is the lateral movement sideways of a ship or boat due to strong winds or currents. Your boat, for example, is traveling in an easterly direction when there is a strong north wind. Your boat will continue to move east, but it will drift (leeway) slightly northward in the water. The phenomenon is most visible at open sea.
Lifejackets: These jackets are buoyant and help you stay afloat. It was very useful in an emergency and should be on every ship and boat.
A lifeboat is a small vessel that can be used to transport the crew and passengers of a ship to a safe place. It is essential to have an adequate supply of lifeboats on board, with emergency supplies and food. Sometimes it’s also used to rescue people in an emergency.
A floating ring device is used to support or rescue a person who falls into the water. It is easily identifiable by its distinctive orange color, white stripes and rope.
Luffing is the act or decision of putting your boat in the direction of the wind. Most commonly, it is used by sailing ships to use the power and direction of the wind in order to cross the sea or channel.
Logbook: A logbook records your actions and activities in real time, ready for future review. This can include events that occur during navigation, control, or operation of a vessel.
Watchperson: Person or crew on duty.
Locker room is the place where all boating and ship gear is kept or stored.
Marine Terminology Beginning with “M”
Mark: When using a chart or navigating on the sea, we use a number of objects as reference points. The object that is used as a point of reference is known as a mark.
Man Overboard: “Man Overboard”, is a term used to describe the situation in which a person, or if he or she has fallen from a ship or boat and into the water. This term is used to signal an emergency and begin rescue operations.
Mast is the vertical pole or pipe that is used to support or secure the sail on a boat. It is mostly used to fit radars and navigational lines on modern ships.
Midship: The middle part of a ship, at a distance equal to the distance between bow and stern.
Mooring is a maritime term used to describe docking, or docking the boat or the ship at the docking station.
Manhole: An opening in a ship’s structure, shell or compartment is called a manhole. The manhole is used for spaces which are difficult to access by the crew.
Marine Terms Beginning with “N”
Navigation is a maritime term used to describe ship operations. It includes the setting of directions, routes, and speed. This can be done on paper, a website, or a computer. When a ship follows its path, the term “navigating” is used.
The nautical mile is the nautical distance on open water. The nautical mile is equal to 1,15 miles or 1,85 miles
Navigation Lights: These lights are installed on boats and ships to indicate their position and heading at night. The main purpose of the navigation light is to prevent accidents and collisions at night. The color of these lights is determined by the area in which they are installed. For example, red represents port, green represents starboard, and white represents stern.
Marine Terminology Beginning with “O”
Oiler: An oiler is a person who assists the watchkeeping officer with his daily duties in the engine room. He performs tasks such as routine maintenance, record keeping, lubrication, cleaning, and other odd jobs that are assigned by the watchkeeping officers.
Overhaul is the process of boat detailing in Perth, disassembling, inspecting, refurbishing and reassembling machinery and equipment aboard a ship. It’s the process of repairing machinery or tools.
Obstruction is anything at sea that forces the ship to change direction. This can include a ship, boat or lifeboat, a shore, port, underwater dangers, or if there is a mark.
Overboard: To jump off a boat or ship.
Outboard motor (also called an external motor): A motor that is attached at the stern of a small boat so the boat doesn’t need to use the rudder to steer the boat. Instead, the motor can be moved to control the boat.
Marine Terms Beginning with “P”
Propeller: A rotating device, similar to a fan, attached to the engine shaft is used to propel a ship forward. It actually pushes or displaces water backward, which then applies force to the ship pushing it forward. The propeller is found on all ships, medium and large boats and even small ones.
Port: This is the term used for both the side of a ship or boat and also a harbor, or any place where ships are loaded or unloaded.
Port bow: This is a term used in marine terminology to describe the left-hand side of a ship or boat.
PFD is the acronym for “Personal Floatation device”. This is a jacket or vest with buoyant properties to help you stay afloat and swim in water.
Pier: A pier connects the sea to land and is used for loading and unloading ships. It allows larger vessels to dock easily, which otherwise would not be able to come close to the land due to a low draft.
Port Hole: A hole in the hull of a ship fitted with a thick window that allows natural light and air into the vessel. They are usually circular with one side strategically hinged.
Port Track is the term used to describe sailing your boat in the forward direction when the wind comes from the port side. It will eventually move your boat to the port.
A pilot is an experienced navigator who has been assigned by port authorities to assist the captain in navigating through the coastal waters around the port. A pilot is well-versed in local conditions, topography and tide patterns.
Marine Terminology Beginning with “R”
Rudder: A flat wooden or metal structure helps to steer the ship. It can also be called a control system fitted to boats, ships and submarines that forces the water in one direction, producing the required thrust.
Rigging is a system that includes sails, masts, ropes and wires.
Radar reflectors: Devices that allow your vessel or boat to be detected on radar systems of other countries from a greater distance. It improves your radar visibility and helps you navigate.
In bad weather, it is sometimes necessary to reduce the area of the sail on sailboats. Reefing is a way to reduce the effective area of a sail to protect it from adverse wind effects.
Rolling is the sideways movement made by a boat or ship around its central axis. The vessel will tilt to port, followed by another tilt in starboard and so on. There is a minimum angle of roll from which a ship can never completely recover without stabilizing equipment.
Run: To let a chain or line move freely.
Radar is an electronic device which uses radio frequency to detect vessels in the vicinity. The device can determine their location, speed and direction in real time. Radar is now on all modern ships to assist with navigation and prevent collisions.
Marine Terminology Beginning with “S”
Scuppers: Drains that drain water directly into the sea from the deck of a boat or ship.
Seamanship is the art and skill of handling a boat and ship properly in all aspects; navigation, maintenance and rigging. Emergency duties, sail handling and record-keeping are also included.
Sextant is a navigation tool used by sailors to find their vessel’s position on sea. It uses the positions of the stars and the moon in the sky. It was once the only way to navigate at sea, but is now only used in emergencies or as a backup.
Skipper: A skipper is the captain or principal pilot of a vessel or boat.
Sounding: The process of sounding is used to check the levels of all the tanks on a ship by lowering the sounding tape. It is the process used to determine the depth of the tank of a boat or ship. The sounding tap is a thin brass band with a bob on the end.
Squall: Sudden change of weather with strong winds and rain.
Starboard: Right side of a ship or boat with the bow facing forward.
Stow: To place an object or item in its designated location on a vessel.
Stern: The rear or back portion of a ship or boat.
Stern Drive: This is a type of propulsion used on boats which combines the best features of both an inboard and an outboard system. The engine is located just beyond the transom, while the drive/propulsion unit is outside.
Saloon: The saloon is a recreational living area on a boat. It is a socializing and meeting place on a boat or ship.
Smoke Room: a designated smoking room on the ship. Smoking is prohibited on board the ship outside of this designated smoke room.
Sidelights are part of navigation lights that use different colored lamps to indicate a specific side of a ship or boat.
Marine Terms Beginning with “T”
Tiller: Bar on which the ship’s rudder can be supported, steered, or turned. It is the handle used to steer a boat with an outboard motor.
Trim is the difference in draft between a vessel’s front and back section. This term is used to describe the net balance of a vessel or ship. If the ship’s trim is by the stern, for example, steps are taken in order to balance the trim.
Tide: The moon’s position and the wind cause water to move in large bodies of water and at sea. The periodic movement of water levels between low and high is known as a tide.
Toe rail is a boat accessory that prevents the crew from falling into the water.
Transom (stern): A cross-sectional view of the boat.
Marine Terminology Beginning with “U & V”.
Underway is a maritime term used to describe a vessel in motion. A ship or boat that is moving on the sea according to the navigation plan.
The vanishing angle is the maximum angle at which a vessel will become dangerously instabile.
Marine Terminology Beginning with “W”
Watchkeeping is the duty that the sailor performs for a specified period. On ships, for example, each officer is required to keep a 4-hour watch.
Waterline: This is a marine term for markings that are placed on the hull of ships and boats to show how far the vessel has submerged in the water.
Weather side: the side of a boat or ship that is exposed to the wind.
Wake: This is the turbulence that occurs in the water when a ship or boat moves forward in water.
Watertight is a term used in the marine industry to describe a surface, door or wall that does not allow water from one side to the other.