Thoroughwort
in botany, the Eupatorium perfoliatum. The stem is round, erect, and hairy; the leaves subsessile, opposite, wrinkled, pale underneath and hairy; the 12 to 15 florets tubular. It grows in bogs in North America. The whole plant is intensely bitter. A decoction of the leaves has been given as a febrifuge. In larger quantities it is emetic, sudorific, and aperient. Called also boneset and cross wort.