any plant of the genus Amaranthus, some species of which are cultivated as food and some for their showy flower clusters or foliage. Compare amaranth family.
Definition: 3
Chemistry. a purplish-red, water-soluble powder, C 20 H 11 N 2 O 10 Na 3 , an azo dye used chiefly to color pharmaceuticals, food, and garments.