Rice, cereal grain [Oryza sativa] of the grass family [Graminae], probably native to the deltas of the great Asian rivers: the Ganges, the Chang [Yangtze], and the Tigris and Euphrates. The plant is an annual, from 2 to 6 ft [61–183 cm] tall, with a round, jointed stem; long, pointed leaves; and edible seeds borne in a dense head on separate stalks. Wild rice is obtained from a different grass plant.