Sorghum bicolor, commonly called sorghum and also known as broomcorn, great millet, Indian millet, Guinea corn, jowar, or milo, is a species in the grass genus Sorghum. It is typically an annual, but some cultivars are perennial. It grows in clumps that may reach over 4 metres (13 ft) high. The grain is 2 to 4 millimetres in diameter.