Definition of prairie smoke in US English:

prairie smoke

noun

  • 1The North American pasque flower, Pulsatilla patens var. multifida, which when flowering en masse gives the effect of a bluish haze.

  • 2A North American avens, Geum triflorum, especially when in fruit (so called from the long plumose hairs on the styles).

Origin

Late 19th century; earliest use found in Journal of American Folklore.