Merriam-Webster Collegiate Dictionary - amaranth

 noun  Etymology: Latin amarantus, a flower, from Greek amaranton, from neuter of amarantos unfading, from a- + marainein to waste away  Date: 1548  1. any of a large genus (Amaranthus of the family Amaranthaceae, the ~ family) of coarse annual herbs including forms cultivated as food crops and various pigweeds  2. a flower that never fades  3. a red azo dye