Small evergreen tree or shrub (Citrus medica). A member of the rue family, citron is cultivated in Mediterranean countries and the West Indies. It has irregular, spreading, spiny branches and large, pale green, broadly oblong leaves. The flowers of the acidic varieties (e.g., the Diamante) are purple on the outside and white on the inside; those of sweet varieties (e.g., the Corsican) are creamy white. The oval or oblong fruit yields firm pulp, either acidic or sweet, that is used only for by-products. The thick peel is cured in brine, candied, and sold as a confection. The fruit of the Etrog variety is used in Jewish religious rites.