USCG Basic Nautical Dictionary

Abaft

behind or further aft

Abeam

At right angles to the centerline of the outside of a ship

Adrift

Loose from moorings or out of place

Aft

in, near, or toward the stern

Aground

Resting on or touching the ground or bottom

Ahead

forward of the bow

All hands

Entire ship's company, both officers and enlisted personnel

Amidships

In the middle portion of ship, along the line of the keel

Anchorage

Suitable place for a ship to anchor. Area of a port or harbor

Anchor Detail

Group of ship's personnel who handle ground tackle when the ship is anchoring or getting underway

Anemometer

Instrument to measure wind velocity

Athwartships

At right angles to the fore and aft of centerline of a ship

Astern

Toward the stern; an object or vessel that is abaft of another vessel or object

Ballast

Heavy weight in the hold of a vessel to maintain proper stability, trim, or draft

Barometer

Instrument that registers atmospheric pressure; used in forecasting weather

Barque

A type of sailing vessel with three (or more) masts, fore-and aft sails rigged on the aftermost mast and square sails rigged on all other masts

Beam

Width; breadth; greatest athwartships width of a vessel

Bearing

Direction of an object expressed in degrees either as relative or true bearing

Belay

To cancel an order; to stop; to firmly secure a line

Bilge

Lower part of vessel where wastewater and seepage collect

Bitt

Strong iron post on ship's deck for working / fastening lines; invariably in pairs

Bitter End

The utmost end of a line

Bow

The forward section of a vessel

Breast Line

A mooring line running at right angles from the ship's fore-and-aft line

Bridge

Raised platform from which the ship is steered, navigated, and conned

Bulkhead

One of the vertical wall-like structures enclosing a compartment

Buoy

Floating marker anchored by a line or chain to a sinker on the bottom which by shape and color conveys navigational information; may be lit or unlit and may be equipped with whistles, bells, gongs, AIS, or RACON

Cardinal Point

One of the four principle points of the compass - north, east, south, west

Carry On

An order to resume work or duties

Chain locker

Compartment in which chain cable is stowed

Cleat

A small metal deck fitting with horns; used for securing lines; also called belaying cleat. Short piece of wood nailed to brow or gangplank to give surer footing

Conn

To direct helmsman as to movement of helm, especially when navigating in narrow channels or heavy traffic

Coxswain

Enlisted member in charge of a boat; acts as helmsman.

Cutter

a Coast Guard vessel 65 feet in length or longer with overnight accommodations; a type of sailing vessel

Damage Control

Measures necessary to keep ship afloat, fighting, and in operating condition

Dead Ahead

Directly ahead of the ship's bow; bearing 000 degrees relative

Deck

On a ship corresponds to the floor of a building on land

Dog

Metal fitting used to secure watertight doors, hatch covers, scuttles, etc.

Double Up

To increase the number of ship-to-pier turns of a mooring line

Draft

Depth of water from the surface to the ship's keel; a detail of crew members

Engineer of the Watch

An officer in charge of the engineering department while on watch

Fake

A single turn of line when line is coiled down

Fantail

Main deck section in the after part of a flush deck ship

Fathom

A six-foot unit of length

Fender

Canvas, wood, rope gear, or old rubber tire used over the side to protect a ship from chafing when alongside a pier or another ship

Fore and Aft

Running in the direction of the keel

Forecastle

Upper deck in the forward part of the ship;

Foul

Jammed, not clear for running

Frame

Ribs of a vessel

Halyard

Line used for hoisting flags, pennants, or balls

Hatch

An opening in the ship's deck for communication or for handling stores and cargo

Hawsepipe

The steel castings in the bow through which anchor cables run

Hawser

Heavy line, 5 inches or more in circumference, used for heavy work

Heave

To throw or toss; to pull on a line

Heel

To list over

Helmsman

The person at the wheel; the person who steers the ship

Hull

Framework of a vessel, together with all her decks, deckhouses, inside plating or planking, but exclusive to masts, rigging, guns, and all superstructure items

Inboard

Toward the ship's centerline

Keel

Backbone of a ship; running from stern to sternpost at the bottom

Knot

One nautical mile per hour; a knot, tie, or fastening formed with rope

Ladder(well)

In a ship corresponds to stairs in a building

Landmark

Any conspicuous object on shore, used for piloting

Lee

Direction away from the wind

Line

Seagoing term for rope or cable

Magazine

Compartment used for stowage of ammunition and explosives

Main Deck

Highest complete deck extending from stern to stern and from side to side

Marlinspike

Pointed iron instrument used in splicing line or wire

Mooring

Securing a ship to a pier, buoy, or another ship; anchoring with two or more anchors

Muster

To assemble the crew; roll call

Nautical Mile

6,076 feet or 2000 yards; one minute of latitude

Officer on Deck/ Officer of the Day

The officer on watch in charge of the ship when moored or anchored

Outboard

Toward the side of the vessel, or outside the vessel entirely

Overhead

on a ship, equivalent to the ceiling of a building ashore

Pilot

An expert who comes on board ships in harbors or dangerous waters to advise the captain as to how the ship should be conned; a person who controls an aircraft

Pitch

The forward heaving and lunging motion of a vessel at sea

Port

Left side of the ship facing forward; a harbor, an opening in the ship's side

Quarter

That part of ship's side near the stern

Rack

A sailor's bed

Roll

Side to side motion of a ship to sea

Rudder

A flat, vertical, mobile structure at the stern of a vessel; used to control the vessel's heading

Running lights / Side lights

Lights required by law to be shown by ship or plane when underway between sunset and sunrise

Screw

The propeller: the rotating bladed device that propels the vessel through the water

Scuttle

Small opening through hatch, deck, or bulkhead to provide access; similar hole in side or bottom of ship; cover for such an opening; to sink a ship intentionally by boring holes in the bottom or by opening sea chest

Secure

To make fast; to tie; an order given on completion of a drill, exercise, or evolution, meaning to withdraw from the corresponding stations and duties

Side Lights

Red and green running lights carried on port and starboard sides, respectively

Slack

The part of a line hanging loose; to ease off, state of the tide when there Is no horizontal movement

Sound

To measure depth of liquids in oil tanks, voids, blisters, and other compartments or tanks

Spring Line

Mooring line leading at an angle of about 45 degrees off centerline of vessel; to turn a vessel with a line

Standby

Preparatory order meaning "get ready" or "prepare to"

Starboard

Right side of a ship looking forward

Stern

After part of a ship

Tide

The vertical rise and fall of the sea caused by gravitational effect of sun and moon

Wardroom

Officers' mess and lounge aboard a ship

Watch

A period of duty, usually of four hours duration

Waterline

Line painted on hull showing point to which ship sinks in water when properly trimmed

Watertight Integrity

System of keeping ship afloat by maintaining water tightness

Weather Deck

Portion of main, forecastle, poop. and upper decks exposed to...