sneezeweed

noun3

1. •
   A plant of the genus Helenium, especially Helenium autumnale.
2. •
   (Australia) A plant of the genus Centipeda; either of the species Centipeda cunninghami or Centipeda minima, which induce sneezing and are known as a folk remedy for colds and allergic reactions.
3. •
   Synonym of sneezewort (Achillea ptarmica).