coneflower

from The American Heritage® Dictionary of the English Language, 5th Edition.

• noun Any of various North American plants of the genera Rudbeckia, Ratibida, and Echinacea in the composite family, having disk flowers on a cone-shaped central receptacle usually surrounded by colorful ray flowers.

from The Century Dictionary.

• noun A name given to certain species of Rudbeckia, coarse composites with conical or columnar receptacles, especially to R. laciniata, which has a greenish-yellow oblong disk, and R. hirta, in which the conical disk is dark-brown.

from the GNU version of the Collaborative International Dictionary of English.

• noun Any plant of the genus Rudbeckia; -- so called from the cone-shaped disk of the flower head. They are cultivated for their large usually yellow daisies with prominent central cones. Also, any plant of the related genera Ratibida and Brauneria, the latter usually known as purple coneflower.
• noun any of various perennials of eastern US having thick rough leaves and long-stalked showy flowers with drooping rays and a conelike center.

from Wiktionary, Creative Commons Attribution/Share-Alike License.

• noun Any of several similar but unrelated flowering plants, of the genera Dracopis, Echinacea, Rudbeckia, and Ratibida, that have a cone-shaped disk of flowers

from WordNet 3.0 Copyright 2006 by Princeton University. All rights reserved.

• noun a wildflower of the genus Ratibida
• noun any of various plants of the genus Rudbeckia cultivated for their large usually yellow daisies with prominent central cones
• noun any of various perennials of the eastern United States having thick rough leaves and long-stalked showy flowers with drooping rays and a conelike center