What is "sneezeweed"

Sneezeweed \Sneeze"weed`\, n. (Bot.) A yellow-flowered composite plant ( Helenium autumnale) the odor of which is said to cause sneezing.

n. 1 (context US English) A plant of the genus (taxlink Helenium genus noshow=1), especially (taxlink Helenium autumnale species noshow=1). 2 (context Australia English) A plant of the genus (taxlink Centipeda genus); either of the species (taxlink Centipeda cunninghamii species) or (taxlink Centipeda minima species), which induce sneezing and are known as a folk remedy for colds and allergic reactions.

n. any of various plants of the genus Helenium characteristically causing sneezing

Sneezeweed is a common name for several plants in the Asteraceae family and may refer to:

• Achillea ptarmica, with white flowers
• Hymenoxys hoopesii, with long yellow petals, native to western North America
• Various species of Helenium, with short yellow petals, native to North and Central America
• In Australia, Centipeda cunninghamii or "old man weed" is also referred to as common sneezeweed