Basic[]
Bow - the front of the boat
Stern - the back of the boat
Port - left when facing the bow
Starboard - right when facing the bow
Bearing Off - Turning the boat away from the wind
Heading Up - Turning towards the wind
(In) Irons - Pointing into the wind
Tacking - Turning the bow of the boat through Irons, sails switch sides
Gybing - Turning the boat so the stern passes through the wind, sails switch sides
Centerboard - a foil extending below the boat to prevent lateral drift, can pivot up into the hull
Daggerboard - a foil extending below the boat to prevent lateral drift
Keel - a foil extending below the boat to prevent lateral drift, with an attached ballast to keep the boat stable
Jib - sail infront of the mast
Mainsail - sail behind the mast
Main sheet - line which controls the mainsail's angle of attack
Boom vang - line which controls the mainsail's twist and leech tension
Jib sheet - rope which controls the jib's angle of attack
Heel - longitudinal roll
Advanced[]
Leeway - difference between apparent heading and course-made-good. allows lift off keel/daggerboard
Leeward - side farthest from the wind
Windward - side closest to the wind
Velocity Header - a lull causing the apparent wind to rotate towards the bow, forces the boat to bear off
Velocity Lift- a gust causing the apparent wind to rotate towards the stern, allows the boat to head up
Header - wind shifts towards the bow forces boat to bear off
Lift - wind shifts towards stern allows boat head up
Lee helm - unbalanced moments between forces from water and forces from air. boat bears off if unchecked
Weather helm - unbalanced moments between forces from water and forces from air. boat heads up if unchecked
Oversteering - pushing the rudder to far, stalling the rudder and resulting in total loss of control.
Spinnaker - third sail hoisted going downwind, doused (taken down) for other points of sail
Slot- gap between main and jib sail, important to have proper air flow, if choked can cause air to stall on the leaward side of the main