coneflower, name for several American wildflowers of the family Asteraceae (aster family). The purple coneflowers (genus Echinacea ), found E of the Rockies, have purple to pinkish petallike rays; some cultivated forms have white flowers. The herb echinacea, derived from the purple coneflower, is taken for colds and other ailments; the plant was used medicinally by Native Americans. Other coneflowers include the yellow coneflowers, or rudbeckias (see black-eyed Susan), and the praire coneflowers (genus Ratibida ), which have yellow or purplish rays. Many species are grown as garden plants. Coneflowers are classified in the division Magnoliophyta, class Magnoliopsida, order Asterales, family Asteraceae.