1. the pigmented, round, contractile membrane of the eye, suspended between the cornea and lens and perforated by the pupil. it regulates the amount of light entering the eye.
2. any of numerous plants of the genus iris, having narrow sword-shaped leaves and showy, variously colored flowers.
3. A rainbow or rainbowlike display of colors.
4. an iris diaphragm.

1. A plant of the genus iris, common in the northern hemisphere, and generally having attractive blooms (wikipedia).
2. the contractile membrane perforated by the pupil, which adjusts to control the amount of light reaching the retina, and which forms the colored portion of the eye (wikipedia).
3. A diaphragm used to regulate the size of a hole, especially as a way of controlling the amount of light reaching a lens.
4. A rainbow, or other colourful refraction of light.
5. A constricted opening in the path inside a waveguide, used to form a resonator.
6. to open or close in the manner of an iris.

1. the goddess of the rainbow, and swift-footed messenger of the gods.
2. the rainbow.
3. an appearance resembling the rainbow; a prismatic play of colors.
4. the contractile membrane perforated by the pupil, and forming the colored portion of the eye. see eye.
5. A genus of plants having showy flowers and bulbous or tuberous roots, of which the flower-de-luce (fleur-de-lis), orris, and other species of flag are examples. see Illust. of flower-de-luce.
6. see Fleur-de-lis, 2.
7. the inner circle of an oscillated color spot.
8. same as iris diaphragm.

1. the rainbow.
2. [capitalized] in classical mythology, the goddess of the rainbow and messenger of the gods, attached especially to hera.
3. [capitalized] the seventh planetoid, discovered by hind at london in 1847.
4. an appearance resembling a rainbow; an appearance of the hues of a rainbow, as seen in sunlit spray, the spectrum of sunlight, etc.; any iridescence.
5. A precious stone.
6. in anatomy, a contraetile colored curtain suspended vertically in the aqueous humor of the eye, between the cornea and the lens, separating the anterior and posterior chambers, which intercommunicate through the pupil.
7. in entomology, the first or inner ring of an ocellated spot, adjoining the pupil, being a light-colored circle with a dark center and outer border.
8. [capitalized] [nl. (Linnæus).] A genus of monocotyledonous plants of the natural order Irideæ, tribe Moræeæ, having the perianth 6-parted, the 3 outer divisions spreading or reflexed, and the 3 inner smaller and erect.
9. A plant of the genus iris.
10. the root of a species of iris cultivated in india and sold in the bazaars of Calcutta to be used, like the florentine orris-root, in perfumery and medicine.
11. the iridescence in fractured pieces of rock-crystal.

1. plants with sword-shaped leaves and erect stalks bearing bright-colored flowers composed of three petals and three drooping sepals
2. diaphragm consisting of thin overlapping plates that can be adjusted to change the diameter of a central opening
3. muscular diaphragm that controls the size of the pupil which in turn controls the amount of light that enters the eye; it forms the colored portion of the eye