- Of or pertaining to a very large natural order of
plants (Rubiaceae) named after the madder (Rubia tinctoria), and
including about three hundred and seventy genera and over four thousand
species. Among them are the coffee tree, the trees yielding peruvian
bark and quinine, the madder, the quaker ladies, and the trees bearing
the edible fruits called genipap and Sierre Leone peach, besides many
plants noted for the beauty or the fragrance of their blossoms.