1) Asterid dicot genus 2) Genus rubia 3) Medicinal plant 4) Plant dye 5) Type genus of the ceae 
Rubia is a genus of flowering plants in the Rubiaceae family. It contains around 80 species of perennial scrambling or climbing herbs and subshrubs native to the Old World. The genus and its best-known species are commonly known as madder, e.g. Rubia tinctorum (common madder), Rubia peregrina (wild madder), and Rubia cordifolia (Indian madder). .....
Rubia is a cultivated variety of potato.
[n] - type genus of the Rubiaceae
genus Rubia noun type genus of the Rubiaceae; Old World herbs and subshrubs grown for their medicinal properties and for dye substances extracted from their roots