Iris (family Iridaceae) A genus of plants that have rhizomes or bulbs, leafy shoots usually flattened in one plane, and showy, characteristic flowers in which the 3 outer perianth segments (the ‘falls’) usually arch down and are larger than the 3 inner perianth segments (the ‘standards’) which are often more or less erect and stalked. The 3 style-branches are broad and petal-like, and forked at the apex. There are some 300 species, throughout the northern temperate zone, many being cultivated (as are many hybrids) for their beautiful flowers.

iris Genus of about 300 species of flowering plants widely distributed, mostly in temperate areas. They are monocotyledons and have bulbs or rhizomes. Height: up to 90cm (3ft). Family Iridaceae. See also crocus; gladiolus