stoneroot

from WordNet (r) 3.0 (2006)

stoneroot
    n 1: erect perennial strong-scented with serrate pointed leaves
         and a loose panicle of yellowish flowers; the eastern
         United States [syn: {horse balm}, {horseweed}, {stoneroot},
         {stone-root}, {richweed}, {stone root}, {Collinsonia
         canadensis}]

from The Collaborative International Dictionary of English v.0.48

Stoneroot \Stone"root`\, n. (Bot.)
   A North American plant ({Collinsonia Canadensis}) having a
   very hard root; horse balm. See {Horse balm}, under {Horse}.
   [1913 Webster]

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