sunflower Any of several annual and perennial plants of the genus Helianthus, native to North and South America. The flower heads resemble huge daisies with yellow ray flowers and a centre disc of yellow, brown, or purple. The seeds yield a useful oil. The common sunflower (H. annuus) has 30cm (1ft) leaves and flower heads more than 30cm (1ft) across; height: to 3.5m (12ft). Family Asteraceae/Compositae.

sun·flow·er / ˈsənˌflou(-ə)r/ • n. a tall North American plant (Helianthus annus) of the daisy family, with very large golden-rayed flowers. Sunflowers are cultivated for their edible seeds, which are an important source of oil for cooking and margarine.

sunflower Annual plant, Helianthus annuus, introduced into Europe from the Americas by the Spanish in 1510.

An important commercial source of edible oil (low in saturates, 12%, approximately 70% polyunsaturated); residual oilseed cake is used as animal feed.

sunflower (Helianthus annuus) See COMPOSITAE.