Iris

i'ris,H.; E. pLluiSES, -ez; L. pi. Irides, ir'T-dez. The rainbow; an appearance resembling the rainbow. {Anat.) A colored membrane at the anterior part of the eye in the midst of the aqueous humor, and perforated by a circular opening called the pupil: see Eye. (Bot.) Flower-de-luce; a tuberous or bulbous-rooted plant, of the flag family, of many varieties, some of which produce flowers of exquisite beauty, and one furnishes orris root. — Irides'cent, -des'ent, «. Having colors like the rainbow. — Irides'cence, -sens, n. Exhibition of colors, etc. — Irid'ium, -T-um, n. (Chem.) One of the metals, the heaviest of known substances.