any of several composite plants of the genus Zinnia, native to Mexico and adjacent areas, esp. the widely cultivated species Z. elegans, having variously colored, many-rayed flower heads.
Origin: 1760–70; < NL, named after J. G. Zinn (1727–59), German botanist; see -ia
zin·ni·a (zĭn'ē-ə) 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.
[New Latin Zinnia, genus name, after Johann Gottfried Zinn (1727-1759), German botanist.]