colicroot

American Heritage® Dictionary of the English Language, Fourth Edition

1. n. Any of certain perennial herbs of the genus Aletris in the lily family, especially A. farinosa of eastern North America, having racemes of small white flowers and rootstocks formerly used in medicine to treat colic. Also called star grass.
2. n. Any of various other plants thought to relieve colic.

Century Dictionary and Cyclopedia

1. n. A name in the United States of several plants having reputed medicinal virtues, as Aletris farinosa, Dioscorea villosa, and Liatris squarrosa.

Wiktionary

1. n. A bitter American herb of the bloodwort family, with small yellow or white flowers in a long spike.

GNU Webster's 1913

1. n. A bitter American herb of the Bloodwort family, with the leaves all radical, and the small yellow or white flowers in a long spike (Aletris farinosa and Aletris aurea). Called sometimes star grass, blackroot, blazing star, and unicorn root.

WordNet 3.0

1. n. any of several perennials of the genus Aletris having grasslike leaves and bitter roots reputed to cure colic
2. n. any of several perennials of the genus Aletris having grasslike leaves and bitter roots reputed to cure colic