Horseradish, a tall herb of the mustard family. It was introduced into North America from Europe. The plant has large, broad leaves with crinkled or toothed edges. Tiny white flowers grow in clusters at the tops of the stems. Horseradish is grown for its tough, white, pungent roots. These are ground and mixed with vinegar, salt, and sugar to make a relish that is used on sandwiches and in sauces, and as a side dish with beef roasts and steak. During the seder, the Jewish ceremonial meal at Passover, horseradish is often used to symbolize the bitter oppression of the Jewish slaves in Egypt.

Horseradish is Armoracia rusticana of the family Cruciferae.