Dictionary.net

• The root of horseradish is frequently used at table; and has long been in the Materia Medica. It is stimulant and diuretic. Externally, it is rubefacient.

1846 - Medical lexicon: a dictionary of medical science
By Robley Dunglison

• The horse radish.

1916 - Appleton's medical dictionary
By Smith Ely Jelliffe