Windward is the side or direction the wind is coming from, and leeward (pronounced “loo-ard”) is the side or direction away from the wind. A boat’s sails normally lie on her leeward side.
The windward side of a boat is the side the wind blows onto. The leeward side, pronounced “loo-ard”, is the side away from the wind. Unlike port and starboard, they are not fixed to the boat: when the boat tacks or gybes, the windward and leeward sides swap over.
On a sailing boat they are easy to tell apart: the sails and the boom normally lie on the leeward side, and when the boat heels, the leeward side goes down towards the water. The crew usually sit on the windward side, where their weight helps hold the boat upright, and the helmsman normally sits there too, where they can see the sails and the water ahead.
The same words describe anything around you:
- A boat or buoy to windward of you is upwind of you, and getting there takes effort, because you have to sail towards the wind.
- Something to leeward is downwind, the easy direction to go.
- A lee shore is a coast downwind of you, onto which the wind is blowing. It is the dangerous side to be on if the engine fails or a sail breaks, so give it plenty of room.
- The lee of an island or a headland is the sheltered water on its downwind side, a good place to anchor or to reef.
The terms appear in the rules of the road. When two sailing boats on the same tack meet, the windward boat keeps clear of the leeward boat (COLREGs Rule 12, and Rule 11 of the Racing Rules of Sailing for boats racing).
More in the book: Chapter 1, The sailing boat