feverweed

[ fee-ver-weed ]
/ ˈfi vərˌwid /

noun

any plant belonging to the genus Eryngium, of the parsley family, especially E. foetidum, of the West Indies, or E. campestre, of Europe.
any of various plants believed to reduce fever.

Origin of feverweed

An Americanism dating back to 1835–45; fever + weed1