Etymology
16th century: horse, meaning "strong," + radish (from Latin radix, "root").

Similarly, the German word Meerrettich literally means "more radish," referring to the strong flavor of horseradish as compared to the garden-variety radish (Raphananus sativus).

General information
Horseradish is a large herbaceous plant that grows 40 to 80 cm (16 to 32") high, a member of the Cruciferae family, originally from Eastern Europe, grown for its hot-flavored root used primarily as a condiment. It contains the same compound (sinigrin) as black mustard. Horseradish has very large lanceolate, often notched, leaves, 10 to 30 cm (4 to 12").