The primary sail on a boat, also called a “main”. On boats with one mast, the mainsail is attached to the aft portion of the mast. On boats with more than one mast, the mainsail is attached to the tallest one.

In a capsize, a boat is pushed onto its side, with its mast parallel to or in the water.”Turtling” describes a capsize in which the boat inverts completely.

This term for downwind sailing can also be a noun or verb. As a noun, it describes either the starboard or port jibe. As a verb, a boat is “jibing” when its stern swings through the wind direction, changing from starboard jib to port.

Leeward is the direction it is blowing to, “downwind”.For rules purposes, the leeward side of a boat is the side the mainsail is on.

Windward is the direction the wind is coming from, “upwind”.