any of a genus (Zinnia) of plants of the composite family, having colorful flower heads, native to North and South America
See zinnia in American Heritage Dictionary 4
(zĭnˈē-ə)
noun
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.