Comfrey

1. A rough, hairy, perennial plant of several species, of the genus Symphytum.
   

A decoction of the mucilaginous root of the “common comfrey” (Symphytum officinale) is used in cough mixtures, etc.; and the gigantic “prickly comfrey” (Symphytum asperrimum) is somewhat cultivated as a forage plant.