Basic Sailing Terms
Following are terms related to the act of sailing. Go here for terms related to sailboats and their equipment.
Apparent wind - The wind felt on a boat (the result of true wind and wind produced by the boat's own motion)
Bearing - A compass direction to a point (such as a waypoint ahead)
Beat - To sail close to the wind (as noun: point of sail close to the wind)
Bend on - To attach a sail to the boom or forestay
Beam reach - The point of sail with the wind coming straight across the beam (from the side)
Broad reach - The point of sail mostly downwind (but not entirely downwind on a run)
Chart - A nautical map showing depths and underwater characteristics
Course - The compass direction in which the boat is being steered (race course: the series of buoys to be rounded in order)
Close-hauled - The point of sail as close to the wind as possible;
Dead reckoning - Navigation and determination of the boat's position based on its direction, speed, and time
Ease - To let out a mainsheet or jibsheet (such as when adjusting a sail)
Ebb tide - The outgoing or falling tide (opposite of Flood tide)
Fix - The boat's position on a chart determined by taking bearings to two or more fixed objects (or as determined by a GPS unit)
Flood tide - The incoming or rising tide (opposite of Ebb tide)
Give way - A vessel that must avoid another vessel that has right of way, under the rules of the road
Gybe (or jibe) - To turn the boat downwind across the wind, with the sails moving from one side to the other
Head off - To turn farther away from the wind
Head up - To turn closer to the wind
Heading - The compass course being steered
Heave-to - To position the boat moving only slowly with the jib backwinded
Heel - The sideways tipping of the boat due to the wind's effect
Hike - To lean far out from the cockpit to help minimize heeling and balance the boat with one's own weight
Holding ground - The bottom under the water in reference to anchoring; for example, "poor holding ground" means the anchor may drag
Hull speed - The theoretical fastest speed of a keelboat that must push water aside rather than plane on top of the water
Jibe - Another spelling for gybe: to turn the boat downwind across the wind, with the sails moving from one side to the other
Jury rig - To fix damaged boat equipment in an improvised way with materials at hand
Knot - A unit of speed (for the boat or the wind) equal to one nautical mile per hour; a nautical mile is 1.15 miles
Lee (or leeward) - A directional term referring to downwind, such as the lee side of the boat or a shore downwind of the boat
Leg - A (usually straight) section of a boat's overall course (in a race or when sailing to a particular destination)
Luffing - A shaking or flapping of the front edge of a sail (the luff) when the sail is let out too far for the course being steered
Make fast - To secure (such as tying off a line)
Nautical mile - see Knot
Offshore - Direction of wind from land toward the water
Onshore - Direction of wind from the water toward the land
Pinching - Sailing too close to the wind when close-hauled; see Points of Sail and Sail Trim
Pitchpole - A type of capsizing when the boat's bow digs into a wave and the boat is flipped forward and over by the next wave
Plane - The boat lifts and sails fast over the surface of the water
Plot - On a nautical (paper or electronic) chart, to draw in the boat's position and course
Point of sail - The direction the boat is pointing relative to wind direction; see diagram here
Reach - A course sailed across the wind, such as a beam reach; see Points of sail
Right of way - According to the rules of the road (navigation laws), the vessel with right of way maintains its present course to avoid collision with another vessel (the give-way vessel)
Route - A term used in chartplotters designating a planned course through a series of waypoints
Rules of the road - Navigation laws specifying which boat must give way to another boat to prevent collision; see Rules of the Road for Sailboats
Run - The point of sail directly downwind; see Points of Sail and Sail Trim
Scope - The ratio of the length of anchor rode that is let out to the water depth; see How to Anchor a Sailboat
Shoal - Shallow
Tack - To turn the boat upwind and across the wind, with the sails moving from one side to the other; see How to Tack a Sailboat
Tail - When using a winch for a halyard or sheet, to tail is to pull on the line behind the winch to maintain pressure on the winch drum
Tender - A boat characteristic of heeling easily; also used to refer to a dinghy used with a larger boat
Trim - In general, to adjust the angle of a sail for greatest efficiency; more specifically, to pull in on the sheet (trim in vs. let out); see How to Trim the Jib
True - With directions, true north is straight up on the chart, as opposed to magnetic north
True wind - The direction the wind comes from not relative to the boat's motion; see Apparent wind
Waypoint - A point marked on a nautical chart (paper or electronic) to assist with navigation (such as to plot a route through a number of waypoints)
Weather helm - The tendency of a sailboat to head up toward the wind when not counteracted by the rudder
Article courtesy of About.com