Cosmos \Cos"mos\, n. (Bot.)
A genus of composite plants closely related to {Bidens},
usually with very showy flowers, some with yellow, others
with red, scarlet, purple, white, or lilac rays. They are
natives of the warmer parts of America, and many species are
cultivated. {Cosmos bipinnatus} and {C. diversifolius} are
among the best-known species; {C. caudatus}, of the West
Indies, is widely naturalized.