Perennial woodland native of North America having a red root and red sap and bearing a solitary lobed leave and white flower in early spring and having acrid emetic properties; rootstock used as a stimulant and expectorant. 原产于北美林地的多年生植物,具红根和红色汁液,早春开白花;根茎被用作刺激物和化痰剂。