radish, herbaceous plant (Raphanus sativus) belonging to the family Cruciferae (mustard family), with an edible, pungent root sliced in salads or used as a relish. It is thought to be native to China; it spread to the Mediterranean area before Greek times and to the New World in the early 16th cent. There are many varieties, with white, red, or black roots of different shapes and sizes, some quite large. Radishes grow easily and quickly throughout temperate regions; they are a staple food in Japan and China, where they are generally pickled in brine. Radishes are classified in the division Magnoliophyta, class Magnoliopsida, order Capparales, family Cruciferae.

horse-radish, perennial herb (Armoracia rusticana, but sometimes classified in other genera) of the family Cruciferae (mustard family), native to central and S Europe (where it has long been cultivated in gardens) and naturalized in many parts of North America. It is grown mainly for its roots, which formerly were used medicinally, particularly as an antiscorbutic. Today the roots make a popular condiment and are usually grated and mixed with vinegar to make a sauce or relish for meats and sea food. The lively pungency of the root is caused by its volatile oil, which resembles mustard oil. The wilted foliage has been used as a poultice to relieve toothache and facial neuralgia. An old name for it is German mustard. Horse-radishes are classified in the division Magnoliophyta, class Magnoliopsida, order Capparales, family Cruciferae.

Annual or biennial plant (Raphanus sativus) of the mustard family, probably of Oriental origin, grown for its large, succulent root. Low in calories and high in bulk, radishes have a sharp taste and are usually eaten raw. The shape of the edible portion of the root varies greatly, as does the color (from white through pink to red, purple, and black). Radishes may weigh only a few ounces (U.S. and European varieties) or, in the case of the Japanese daikon, more than 2 lbs (1 kg).

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