[1] : The Collaborative International Dictionary of English v.0.48

zinnia \zin"nia\, n. nl. so called after professor zinn, of
   g"ottingen. bot.
   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.
   1913 webster
see also:
zinnia zinnia elegans 

[2] : WordNet (r) 2.0

zinnia
     n : any of various plants of the genus zinnia cultivated for
         their variously and brightly colored flower heads syn: old
         maid, old maid flower
see also:
old maid old maid flower 

Zinnia >> Z Words
Zinnia, definition of term: Zinnia
zinnia_pag1.html