The Collaborative International Dictionary of English v.0.48:

Bloodroot \Blood"root`\, n. (Bot.)
   A plant (Sanguinaria Canadensis), with a red root and red
   sap, and bearing a pretty, white flower in early spring; --
   called also puccoon, redroot, bloodwort, tetterwort,
   turmeric, and Indian paint. It has acrid emetic
   properties, and the rootstock is used as a stimulant
   expectorant. See Sanguinaria.
   [1913 Webster]

   Note: In England the name is given to the tormentil, once
         used as a remedy for dysentery.
         [1913 Webster]

The Collaborative International Dictionary of English v.0.48:

Bloodwort \Blood"wort`\, n. (Bot.)
   A plant, Rumex sanguineus, or bloody-veined dock. The name
   is applied also to bloodroot (Sanguinaria Canadensis), and
   to an extensive order of plants (H[ae]modorace[ae]), the
   roots of many species of which contain a red coloring matter
   useful in dyeing.
   [1913 Webster]

WordNet (r) 3.0 (2006):

bloodwort
    n 1: any of various plants of the family Haemodoraceae; roots
         contain a deep red coloring matter