rhubarb . ( Of the lat. )( rheubarbarum ). 1. m. herbaceous, perennial plant of the family of the Poligonáceas, with radicals, large, petiolate, toothed and sinuous rim leaves, rough above, nervudas and hairy below, yellow or green, small flowers in spikes on a scape fistuloso and foldout. Measure of one to two meters in height, has dry fruit, of a single triangular seed and Rhizome Brown on the outside, red with white dots in the interior, compact and bitter taste. He lives in central Asia and the root is widely used in medicine as purgative. 2. m. root of this plant. rhubarb white. 1. m. mechoacán.