In geography and seamanship, Windward () and leeward () are directions relative to the wind. Windward is upwind from the point of reference, i.e. towards the direction from which the wind is coming; leeward is downwind from the point of reference, i.e. along the direction towards which the wind is going.

The side of a ship that is towards the leeward is its "lee side". If the vessel is heeling under the pressure of crosswind, the lee side will be the "lower side". During the Age of Sail, the term weather was used as a synonym for windward in some contexts, as in the weather gage.

Since it captures rainfall, the windward side of a mountain tends to be more moist than the leeward side it blocks. Such a drier leeward area is called a rain shadow.