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Nautical Terms

Nautical Terms

  • There are many nautical terms we have listed a few that are commonly used among boaters. It is good practice to use the correct terms.
    The operator yells back to you “cleat that line on the right side”. If you are facing aft (toward the stern) you may cleat it off on your right side which is actually the left or port side of the boat. If he had said “cleat it on the starboard side” (the right side when facing forward) there would be no confusion.
    Abaft Toward the stern
    Abeam To the side of the vessel
    Astern Toward the stern
    Beam Width of the boat at the widest point.
    Bearing Direction of an object from the observer.
    Berth 1. Bed on board a boat.
    2. A position where the vessel is made fast to a dock.
    Bilge Lowest portion of a vessel inside the hull.
    Bollard Large strong fitting on dock usually iron used to fasten mooring lines.
    Bow Forward section of the boat.
    Breakwater Structure built usually of rocks to create a protective barrier wall from heavy seas.
    Bulkhead A vertical wall in the hull.
    Burgee Small flag to indicate the identity of a club or organization
    Cast off Remove all lines from a vessel in preparation of departure
    Channel Navigable portion of a waterway usually marked with buoys.
    Chart Detailed map of the waterway including land and buoys
    Chine The intersection of where the topsides and the bottom of the hull.
    Chock U shaped fitting on the deck to position a mooring line.
    Cleat Fitting to which mooring lines are tied.
    Course Direction vessel is to be steered.
    Deadrise The angle formed by a horizontal line at the keel and the angle of the bottom of the boat as it rises upward from horizontal.
    Deviation Compass error from pointing to magnetic north.
    Dolphin Small group of piles sticking out of the water fastened together for strength.
    Draft The vertical distance from the water line to the lowest part of the boat.
    Ease Let out line slowly while in control of it.
    Ebb Out going (toward the sea) flow of tidal current.
    Fathom Linear measurement of 6 feet.
    Forward Toward the front or bow of the vessel.
    Freeboard The vertical distance between the waterline and the top of the deck
    Galley kitchen on the vessel.
    Ground Swells Waves that become shorter and steeper as the approach shore or shallow water.
    Ground Tackle Rode (chain and/or line) ,anchor, and shackles (Anchor and gear).
    Gunwale Pronounced Gun-el. The upper edge of the side of the boat.
    Head The toilet on board the vessel.
    Helm Steering gear i.e wheel or tiller.
    Hull Test
    Keel Main structural member beneth the hull to provide steering stability and reduce leeway.
    Knot 1. General term for a hitch or bend in a line.
    2. One nautical mile per hour.
    Leeway Sideways drift of a boat caused by wind or current.
    Length Overall (LOA) Length from the tip of the bow to the end of the stern not including anything bolted to the hull.
    Line Rope used on board a vessel.
    MAYDAY Radio distress call.
    Midships Near center of the vessel.
    Moored Anchored or tired to a dock or pier.
    Mooring A permanent anchor usually marked by a round mooring buoy.
    PFD Life preserver (Personal Floatation Devise)
    Pile Pole usually wood driven into the bottom to be used to support a dock or aid to navigation.
    Pitch 1. Rise and fall of the bow as the vessel moves through the water.
    2. The theoretical distance a propeller will advance forward in one revolution.
    Port Left Side of the boat facing forward. (PORT and LEFT both have 4 Letters)
    Pulpit Forward railing structure at the bow.
    Quay A wharf or pier parallel to the water’s edge for loading and unloading cargo.
    Radar Electronic system to determine the position of objects at night and in reduced visibility.
    Rode Line and chain connected to the anchor.
    Roll Alternating motion of a boat leaning alternately from port to starboard.
    Saloon Pronounced Sal-on The main cabin of the vessel.
    Scope The ratio of length of anchor rode in use to the vertical distance from the bow of the vessel to the bottom of the water.
    Screw Propeller
    Scupper Drain holes in the deck.
    Sea Anchor Parachute shaped devise used in deep open water to keep a vessels bow into the wind and waves and reduce drift.
    Shipshape Vessel kept well organized and in good working order.
    Starboard Right side of the boat facing forward.
    Stateroom Sleeping Quarters for guest or captain.
    Stem The forward member of the hull
    Stern Aft section of the boat.
    Stow Put in proper place.
    Stuffing Box A through hull fitting for the propeller shaft or rudder post.
    Superstructure Cabins and other structures above deck.
    Swell Long large wave.
    Tides The vertical rise and fall of water caused by gravitational forces of the sun and moon.
    Topsides The sides of the vessel above the water line.
    Transom The transverse part of the stern.
    Transom Vertical section at the stern.
    Variation difference between true geographic north and magnetic north.
    Vessel Any craft used for transportation on the water.
    VHF radio Very High Frequency radio used for communication.
    Wake Waves created by the passing of another vessel.
    Wharf A structure parallel to the shore for docking.
    Windage Wind resistance.
    Windlass A rotating drum for hauling in line (like anchor line).
    Windward The direction from which the wind is blowing.
    Yaw To swing or steer off course.
    Reference Chapman Piloting


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