zinnia

American Heritage® Dictionary of the English Language, Fourth Edition

1. n. Any of various plants of the genus Zinnia, native to tropical America, especially Z. elegans, widely cultivated for its showy, rayed, variously colored flower heads. Also called regionally old maid, old maid flower.

Century Dictionary and Cyclopedia

1. n. A genus of composite plants, of the tribe Helianthoideæ, type of the subtribe Zinnieæ. It is characterized by solitary radiate flower-heads with a conical or cylindrical receptacle, the flowers both of the disk and ray being fertile, and those of the ray almost or quite without a tube, and persistent upon the ripened achene; the achenes of the inner flowers each bear from one to three awns. There are 12 species, natives of Mexico, Texas, and Arizona, 2 of which, long cultivated in gardens, are now widely naturalized. They are annuals, perennials, or sometimes shrubby plants, bearing opposite entire leaves and rather large and showy flower-heads peduncled at the ends of the branches or in the forks between them. Five species occur within the United States, mostly with light-yellow or sulphur-colored rays. The cultivated species are chiefly of various shades of deep red; they have been called youth-and-old-age, from the lasting and somewhat rigid rays and the continued production of new disk-flowers; but are more usually known by the generic name zinnia, especially in the common double form.
2. n. [lowercase] A plant of this genus.

Wiktionary

1. n. Any of several brightly coloured flowering plants, of the genus Zinnia, native to tropical America; old maid

GNU Webster's 1913

1. n. Any plant of the composite genus Zinnia, Mexican herbs with opposite leaves and large gay-colored blossoms. Zinnia elegans is the commonest species in cultivation.

WordNet 3.0

1. n. any of various plants of the genus Zinnia cultivated for their variously and brightly colored flower heads