acres

An acre is a unit of area commonly used in land measurement in the United States, Canada, the United Kingdom, and other countries with historical ties to the British imperial system. It is a non-SI unit defined as exactly 43,560 square feet, equal to 4,840 square yards or about 4,046.856 square meters. In metric terms, one hectare equals 2.47105 acres, and one acre equals about 0.404686 hectares.

The term derives from Old English æcer, meaning a field. Historically, the acre described the area a yoke of oxen could till in a day and is commonly defined as a rectangle 660 feet by 66 feet (a furlong by a chain), totaling 43,560 square feet.

Usage and context: Acres remain widely used for farmland, real estate, and rural planning, particularly in the United States and parts of the English-speaking world. Many other countries employ hectares for official land measurements, with one hectare equaling about 2.471 acres. For quick context, a square mile contains 640 acres. The acre serves as a practical, legacy unit for describing moderately large land areas in regions where metric measurements are not universally adopted.