wind + weard

Windward combines 'wind' (from Old English wind, related to Latin ventus) and the suffix '-ward' (from Old English weard, meaning in the direction of). Windward means facing the wind. The word is transparently English and has been in use since at least the 1300s in sailing vocabulary. The windward side of a ship faces the wind. The windward side of an island faces the prevailing trade winds.

In the Caribbean, the distinction between windward and leeward determined everything. The Windward Islands — Dominica, Martinique, Saint Lucia, Barbados, Grenada — face the northeast trade winds. The Leeward Islands — Antigua, Saint Kitts, Montserrat, Guadeloupe — are sheltered from them. The names were given by Spanish and then English sailors based on the approach from Europe: the Windward Islands were the first encountered when sailing with the wind.

On any single island, the windward side receives more rain. The trade winds push moisture-laden air against the island's mountains, forcing it upward where it cools and condenses. The windward slopes are wet, green, and covered in rainforest. The leeward slopes are dry, brown, and sometimes nearly arid. A mountain that rises 1,000 meters can create a desert on one side and a jungle on the other. The word windward describes half of that equation.

Sailors use windward constantly. Racing yachts try to sail as close to windward as possible — the ability to point into the wind is a measure of a boat's performance. 'To windward' is the direction from which the wind blows. 'To leeward' is the direction it blows toward. Everything in sailing starts with knowing which side is windward.