[bohn-set] 
| any composite plant of the genus Eupatorium, esp. E. perfoliatum, of North America, having white flowers in a flat-topped cluster. |
| bone·set (bōn'sět') n. Any of several plants of the genus Eupatorium in the composite family, especially the eastern North American species E. perfoliatum, having opposite leaves united around the stem and clusters of small white flower heads. Also called thoroughwort. [From its use as a folk medicine.] |
| thor·ough·wort (thûr'ō-wûrt', -wôrt', thûr'ə-, thŭr'-) n. See boneset. [thorough, through (from the fact that its branches appear to grow through the leaves) + wort1.] |
thoroughwort
any of about 40 species of herbaceous plants constituting the genus Eupatorium of the composite family Asteraceae, native primarily to tropical America. The North American plant known as boneset is E. perfoliatum, also known as agueweed and Indian sage. It is common in wet places and is a coarse, rough, hairy perennial about 0.6 to 1.8 metres (2 to 6 feet) high. Its lance-shaped, toothed, and wrinkled leaves are joined together at their bases around the stem. In August the plants bear small, tubular, white flowers in numerous heads that form a flat and branched cluster
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