honewort

from The American Heritage® Dictionary of the English Language, 5th Edition.

• noun Any of several plants in the parsley family having umbels of small white flowers, especially Cryptotaenia canadensis of North America and East Asia and Trinia glauca of Eurasia.

from The Century Dictionary.

• noun A name applied to several umbelliferous plants, as Sison Amomum, the stone-parsley, Trinia vulgaris, and Cryptotœnia Canadensis: so named because formerly used to cure the swelling called a hone.

from the GNU version of the Collaborative International Dictionary of English.

• noun (Bot.) An umbelliferous plant of the genus Sison (Sison Amomum); -- so called because used to cure a swelling called a hone.

from Wiktionary, Creative Commons Attribution/Share-Alike License.

• noun Either of two plants of the family Umbelliferae