any of several North American plants of the genus Rudbeckia, esp R. hirta, having flower heads of orange-yellow rays and brown-black centres: family Asteraceae (composites)
a composite plant, Rudbeckia triloba, of the southeastern U.S., having a single flower with yellow rays darkening to an orange orbrown at the base and a brownish-black disk.
any North American plant of the genera Rudbeckia, Ratibida, and Echinacea, which have rayed flowers with a conelike centre: family Asteraceae (composites)
