Amaranthus, collectively known as amaranth, is a cosmopolitan genus of annual or short-lived perennial plants. Some amaranth species are cultivated as leaf vegetables, pseudocereals, and ornamental plants. Most of the Amaranthus species are summer annual weeds and are commonly referred to as pigweed. Catkin-like cymes of densely packed flowers grow in summer or autumn. Approximately 60 species are recognized, with inflorescences and foliage ranging from purple, through red and green to gold. Members of this genus share many characteristics and uses with members of the closely related genus Celosia. "Amaranth" derives from Greek ἀμάραντος (amárantos), "unfading", with the Greek word for "flower", ἄνθος (ánthos), factoring into the word's development as amaranth. Amarant is an archaic variant.