Maize (Zea mays L. ssp. mays; also known as corn) is a cereal grain that was domesticated in Mesoamerica and then spread throughout the American continents. Maize spread to the rest of the world after European contact with the Americas in the late 15th century and early 16th century. The term maĆze derives from the Spanish form of the Arawak Native American term for the plant. However, it is commonly called corn in the United States, Canada and Australia. Corn is a shortened form of "Indian corn", i.e. the Indian grain. The English word "corn" originally referred to a granular particle, most commonly cereal grains. Hybrid maize is preferred by farmers over conventional varieties for its high grain yield, due to heterosis ("hybrid vigor"). Maize is the largest crop in all of the Americas (270 million metric tons annually in the U.S. alone).
While some maize varieties grow 7 metres (23 ft) tall at certain locations, commercial maize has been bred for a height of 2.5 metres (8 ft). Sweetcorn is usually shorter than field-corn varieties.