SailMB Open App

Sailing Terms,
in plain language.

Every sport has its own language, and sailing has more than most. Here is the start-line vocabulary, the points of sail, and the racing rules you will meet in your first few races, without the gatekeeping.

A starter set of the terms that matter most in SailMOB. The full glossary lives inside the game, where every term pops up right when you need it. Jump in and see them in action.

Know the words? The guides show what to do with them in a race.

Getting Oriented

Regatta

A sailing competition made up of a series of races, scored together to decide an overall winner.

your club season, a championship, the Olympics – all regattas. The races SailMOB drills are the building blocks of one.

Three frames side by side, labeled RACE 1, RACE 2 and RACE 3, each with the wind blowing from the top. In each, the same two boats, one red and one blue, sail upwind one ahead of the other: the red boat leads in races 1 and 3, and the blue boat in race 2.

Try it in the Rules Lab

Port & Starboard

Port is the left side of the boat as you face forward; starboard is the right.

a boat on starboard tack almost always has right of way, which is why "Starboard!" is the loudest word on the course.

Two boats sailing upwind on opposite tacks, converging, with the wind blowing from the top of the frame. The blue boat on the left, labeled PORT in amber, is on port tack and must keep clear. The red boat on the right, labeled STBD in green, is on starboard tack and holds right of way.

Try it in the Rules Lab

Windward & Leeward

Windward is the side the wind hits first; leeward is the sheltered side the wind blows toward.

when two boats overlap, the leeward one usually has rights over the windward one.

Two boats on starboard tack sailing upwind side by side, overlapped, with the wind blowing from the top of the frame. The red boat, labeled LEE in green, is the leeward boat and holds right of way. The blue boat, labeled WIND in amber, is the windward boat and must keep clear.

Try it in the Rules Lab

Tack

Which side the wind is coming over. Starboard tack means the wind is over the starboard side; port tack means it is over the port side.

knowing your tack tells you instantly who has right of way in a crossing.

Two boats on starboard tack sailing upwind, with the wind blowing from the top of the frame, each trailing a dotted line of the track it has sailed. The red boat has held a straight course. The blue boat, labeled TACKED in amber, came in on port tack: its track runs up to the right, then hooks round through the wind onto starboard, parallel to the red boat.

Try it in the Rules Lab

Points of Sail

No-Go Zone

The roughly 45-degree wedge straight upwind where a boat cannot make power and the sails just flap.

steer in here and you stall. Bear away to fill the sails and get moving.

A blue boat pointing straight up into the wind, which blows from the top of the frame. Its sails hang slack along the centerline. A red shaded wedge opens upward from the boat, labeled NO-GO ZONE, its two dashed edges marked 45 degrees either side of the wind: no boat can sail a course inside it.

Try it in the Rules Lab

Close-Hauled

Sailing as close to the wind as you can while keeping the sails full and the boat moving.

your upwind gear, the angle you hold on every beat to the windward mark.

A red boat on starboard tack, labeled STBD in green, sailing upwind with the wind blowing from the top of the frame. It sails close-hauled, as near the wind as it can point, heading up and to the left with its sails trimmed in tight.

Try it in the Rules Lab

Beam Reach

Sailing with the wind hitting the boat square on the side, at about 90 degrees.

usually the fastest, easiest point of sail.

Two boats sailing across the frame toward the left, with the wind blowing from the top, square onto their starboard sides. Their sails are eased about halfway out, toward the bottom of the frame. The red boat sails just upwind of the blue boat.

Try it in the Rules Lab

Broad Reach

Sailing with the wind coming from behind and off to one side.

fast and stable, and where an asymmetric spinnaker really lights up.

Two boats on starboard tack sailing downwind toward the bottom left, with the wind blowing from the top of the frame, so it comes from behind them and over their starboard side. Their sails are eased well out to the left. The red boat sails upwind of the blue boat.

Try it in the Rules Lab

Run

Sailing dead downwind, with the wind straight behind you.

often slower than a broad reach, because the apparent wind drops away.

Two boats, one red and one blue, sailing straight down the frame side by side, with the wind blowing from the top, directly behind them. Their sails are let all the way out to the side, square to the wind.

Try it in the Rules Lab

Reading the Wind

True Wind

The real wind over the water: the speed and direction you would feel standing still.

this is what the weather is doing, no matter how fast you sail.

Two boats on starboard tack, one red and one blue, sailing upwind side by side, with the wind blowing from the top of the frame. A long white arrow comes straight down into each boat, labeled TRUE WIND 12 KT: the wind as it blows over the water, whatever the boats are doing.

Try it in the Rules Lab

Apparent Wind

The wind you actually feel on a moving boat, a blend of the true wind and the wind your own motion creates.

it shifts forward as you speed up, which is why you trim in as you accelerate.

Two boats, one red and one blue, sailing downwind, with the wind blowing from the top of the frame. Each boat has two arrows pointing into it: a dashed white arrow labeled TRUE coming straight from the top, and a shorter solid yellow arrow labeled APPARENT coming from further toward the bow.

Try it in the Rules Lab

Lift

A wind shift that lets you point closer to the mark without changing course.

a free shortcut. Stay on the lifted tack and ride it.

A red boat on starboard tack after the wind has swung 20 degrees clockwise. Drawn out from the boat: an orange arrow labeled TO MARK, a dashed white line labeled BEFORE for its close-hauled course before the shift, and a solid green line for its course now, swung toward the mark. A green arc runs from the old course to the new one, and green text reads LIFTED 20 degrees.

Try it in the Rules Lab

Puff

A patch of stronger wind moving across the water, often visible as a dark ripple.

spot them early and use them to accelerate.

A puff on the water: a broad band of darker water, flecked with white where the breeze is stronger, running down the frame the way the wind blows, from the top, with lighter water either side of it. Two boats, one red and one blue, sail downwind inside the band.

Try it in the Rules Lab

Wind Shadow

The patch of disturbed, slower air a boat leaves downwind of its sails.

park a rival in your shadow to slow them, and stay out of everyone else's.

Two boats on starboard tack sailing downwind toward the bottom left, sails eased well out, with the wind blowing from the top of the frame. A lighter cone of wind shadow fans out downwind from the blue boat, toward the bottom of the frame, and the red boat sits inside it.

Try it in the Rules Lab

Speed & Tactics

VMG

Velocity Made Good: how fast you are actually closing on the next mark, once your sailing angle is taken into account.

fast in the wrong direction loses to slower and pointed right. The HUD shows it live.

A red boat on starboard tack sailing upwind with the wind blowing from the top of the frame. From its bow a dashed white arrow along its heading reads SPEED 5.7 KT. A shorter solid green arrow pointing straight up into the wind reads VMG 3.8 KT: the part of that speed that carries the boat upwind.

Try it in the Rules Lab

Layline

The line you can sail straight to a mark on your current tack without tacking again.

hit it too early and you overstand, sailing extra distance for nothing.

The windward mark, an orange buoy labeled MARK, with its two laylines drawn as dashed lines running downwind from it: green for starboard tack toward the bottom right, red for port tack toward the bottom left. The wind blows from the top of the frame. A blue boat on starboard tack sails up the green layline, straight for the mark.

Try it in the Rules Lab

Dirty Air

Turbulent, slowed air in the wake of another boat's sails.

sit directly behind someone and your speed bleeds away. Find a clear lane.

Two boats on starboard tack sailing upwind, close-hauled, with the wind blowing from the top of the frame. A lighter cone of disturbed wind fans out downwind from the red boat ahead, and the blue boat behind sails right inside it.

Try it in the Rules Lab

Lee Bow

Tacking just ahead and to leeward of a rival so your bad air blows back over their sails.

one of the strongest attacking moves upwind. It forces them to tack away.

Two boats on starboard tack sailing upwind about a boat length apart, with the wind blowing from the top of the frame. The red boat, labeled LEE BOW in green, sits just ahead and to leeward of the blue boat, labeled WIND in amber. A pale fan spreads from the red boat's windward side across the blue boat, and three curved white arrows run from the red boat onto the blue boat's sails: the red boat's backwind.

Try it in the Rules Lab

Covering

Staying between a rival and the next mark, or the wind, to keep yourself ahead.

the classic move when you are leading and want to stay there.

The windward mark, an orange buoy labeled MARK, at the top left, with the wind blowing from the top of the frame. Two boats on starboard tack sail upwind toward it, close-hauled. The red boat, labeled AHEAD in green, sits between the mark and the blue boat, labeled ASTERN in amber. A lighter band of disturbed wind trails back from AHEAD and falls across ASTERN.

Try it in the Rules Lab

The Rules

Clear Astern

A boat is clear astern when she's entirely behind a line square across the stern of the boat ahead.

on the same tack and not overlapped, the boat catching up from behind has to keep clear (rule 12).

Two boats on starboard tack sailing upwind, close-hauled, one behind the other, with the wind blowing from the top of the frame. The red boat ahead is labeled AHEAD in green. A yellow dashed line runs square across its stern, and the blue boat behind, labeled CLEAR ASTERN in amber, is entirely behind that line.

Try it in the Rules Lab

Right of Way

The boat with rights holds its course; the other boat has to keep clear.

starboard over port, leeward over windward. The whole fleet sails by it.

Two boats on opposite tacks crossing, with the wind blowing from the top of the frame. The red boat, sailing upwind on starboard tack, carries a green tag reading RIGHT OF WAY. The blue boat, on port tack, carries an amber tag reading KEEP CLEAR, and a dotted line shows its track: it sailed up on port, then bore away to duck behind the red boat's stern.

Try it in the Rules Lab

The Zone

The circle three boat lengths out from a mark, where mark-room rights lock in.

whether your bow is ahead of a rival's the moment you reach it decides who gets room.

A windward mark, an orange buoy labeled MARK, at the center of its zone, a circle three boat lengths out drawn as a white dashed ring with a light fill. Two boats on starboard tack, overlapped, are just reaching the edge of the circle, with the wind blowing from the top of the frame. The red boat, labeled INSIDE in green, is nearer the mark. The blue boat, labeled OUTSIDE in amber, is farther out.

Try it in the Rules Lab

Mark-Room

The room an inside boat is owed to round a mark, if it had the overlap entering the zone.

win the overlap early and you can lock a rival out of the rounding.

A windward mark, an orange buoy labeled MARK, inside its zone, three boat lengths out, drawn as a white dashed circle with a light fill, with the wind blowing from the top of the frame. Two boats on starboard tack sail up to the mark from below, both inside the zone. The red boat, labeled INSIDE in green, is closest, its bow alongside the mark, about to round it with the mark on its port side. The blue boat, labeled OUTSIDE in amber, sails about a boat length farther out, leaving the inside boat room.

Try it in the Rules Lab

OCS

On Course Side: over the start line early, before the gun.

you have to dip back and restart, which can cost you the whole first leg.

The start line at the gun, a yellow dashed line across the frame, with the wind blowing from the top. The blue boat, labeled OCS in amber, is above the line on the course side, over early. The red boat, labeled CLEAR in green, is below the line on the pre-start side.

Try it in the Rules Lab

Penalty Turn

A spin of the boat, one or two full turns, taken to clear a foul instead of being scored out.

costs a few boat lengths, far cheaper than a disqualification.

A red boat sailing away to the right, with the wind blowing from the top of the frame. The dotted line of the track it has sailed loops round twice behind it: two full turns the same way round, each through one tack and one jibe.

Try it in the Rules Lab

Barging

Trying to force in at the committee-boat end of the start line with no room and no right to it.

almost always ends in a foul. Do not be that boat.

The committee-boat end of the start line, a yellow dashed line running in from the left to the committee boat, a white boat flying a flag and labeled COMMITTEE, with the wind blowing from the top of the frame. The red boat, labeled LEE in green, sails close-hauled on starboard just below the line, its bow tucked up at the committee boat with no gap left. The blue boat, labeled BARGER in amber, sits to windward and astern of LEE. A dashed blue arrow runs from its bow into the closed gap between LEE and the committee boat, crossed out with a red X.

Try it in the Rules Lab

Learn them by sailing them.

Reading is one thing. Calling for room at the zone with three boats on your hip is another.

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