any of a genus of herbaceous plants, some of which are grown in gardens for their its showy purple flowers: genus Amaranthus
a dark reddish purple colour
a red dye used to colour medicines and foodstuffs
chiefly literary an imaginary flower that never fades
amaranthine /-ʹranthin, -thien/ adj
[Latin amarantus, a flower, from Greek amaranton, neuter of amarantos unfading, from a-2 + marainein to waste away]