Noun
Any of several plants grown as leaf vegetables:
Ipomoea aquatica, water spinach, a semi-aquatic plant with hollow stems and long, lance-shaped leaves.
Amaranthus dubius, often bearing red or purple marks
Amaranthus tricolor, edible amaranth
Basella alba, Malabar spinach, with thick, succulent, heart-shaped leaves
Source: en.wiktionary.org