'Helianthus annuus' definitions:

Definition of 'Helianthus annuus'

From: WordNet
noun
Annual sunflower grown for silage and for its seeds which are a source of oil; common throughout United States and much of North America [syn: common sunflower, mirasol, Helianthus annuus]

Definition of 'Helianthus annuus'

From: GCIDE
  • Sunflower \Sun"flow`er\, n. Any plant of the genus Helianthus; -- so called probably from the form and color of its flower, which is large disk with yellow rays. The commonly cultivated sunflower is Helianthus annuus, a native of America. [1913 Webster]