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iris
i·ris / ˈīris/ • n. 1. a flat, colored, ring-shaped membrane behind the cornea of the eye, with an adjustable circular opening (pupil) in the center. ∎ (also iris diaphragm) an adjustable diaphragm of thin overlapping plates for regulating the size of a central hole, esp. for the admission of light to a lens. 2. a plant with sword-shaped leaves and showy flowers, typically purple, yellow, or white. Native to both Eurasia and North America, it is widely cultivated as an ornamental. • Genus Iris, family Iridaceae (the iris family): many species and numerous hybrids, including the crested dwarf iris (I. cristata) and the sweet iris (I. pallida). The iris family also includes the gladioli, crocuses, and freesias. 3. a rainbow or a rainbowlike appearance. • v. [intr.] (of an aperture, typically that of a lens) open or close in the manner of an iris or iris diaphragm. |
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"iris." The Oxford Pocket Dictionary of Current English. 2009. Encyclopedia.com. 11 Feb. 2012 <http://www.encyclopedia.com>. "iris." The Oxford Pocket Dictionary of Current English. 2009. Encyclopedia.com. (February 11, 2012). http://www.encyclopedia.com/doc/1O999-iris005.html "iris." The Oxford Pocket Dictionary of Current English. 2009. Retrieved February 11, 2012 from Encyclopedia.com: http://www.encyclopedia.com/doc/1O999-iris005.html |
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iris
iris The pigmented ring of muscular tissue, lying between the cornea and the lens, in the eyes of vertebrates and some cephalopod molluscs. It has a central hole (the pupil) through which light enters the eye and it contains both circular and radial muscles. Reflex contraction of the former occurs in bright light to reduce the diameter of the pupil (see pupillary reflex); contraction of the radial muscles in dim light increases the pupil diameter and therefore the amount of light entering the eye. Colour is determined by the amount of the pigment melanin in the iris. Blue eyes result from relatively little melanin; grey and brown eyes from increasingly larger amounts.
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"iris." A Dictionary of Biology. 2004. Encyclopedia.com. 11 Feb. 2012 <http://www.encyclopedia.com>. "iris." A Dictionary of Biology. 2004. Encyclopedia.com. (February 11, 2012). http://www.encyclopedia.com/doc/1O6-iris.html "iris." A Dictionary of Biology. 2004. Retrieved February 11, 2012 from Encyclopedia.com: http://www.encyclopedia.com/doc/1O6-iris.html |
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iris
iris (I-ris) n. the part of the eye that regulates the amount of light that enters. It forms a coloured muscular diaphragm across the front of the lens; light enters through a central opening (the pupil). Contraction of different sets of muscles of the iris causes the pupil to dilate in dim light and to contract in bright light. i. bombé an abnormal condition of the eye in which the iris bulges forward towards the cornea.
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"iris." A Dictionary of Nursing. 2008. Encyclopedia.com. 11 Feb. 2012 <http://www.encyclopedia.com>. "iris." A Dictionary of Nursing. 2008. Encyclopedia.com. (February 11, 2012). http://www.encyclopedia.com/doc/1O62-iris.html "iris." A Dictionary of Nursing. 2008. Retrieved February 11, 2012 from Encyclopedia.com: http://www.encyclopedia.com/doc/1O62-iris.html |
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Iris
Iris Asteroid 7, discovered in 1847 by the English astronomer John Russell Hind (1823–95). Iris is an S-class asteroid, of diameter 208 km. Its mean magnitude at opposition is 8.4; of the main-belt asteroids, only Vesta, Ceres, and Pallas can become brighter. Its orbit has a semimajor axis of 2.386 AU, period 3.69 years, perihelion 1.84 AU, aphelion 2.93 AU, and inclination 5°.5.
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"Iris." A Dictionary of Astronomy. 1997. Encyclopedia.com. 11 Feb. 2012 <http://www.encyclopedia.com>. "Iris." A Dictionary of Astronomy. 1997. Encyclopedia.com. (February 11, 2012). http://www.encyclopedia.com/doc/1O80-Iris.html "Iris." A Dictionary of Astronomy. 1997. Retrieved February 11, 2012 from Encyclopedia.com: http://www.encyclopedia.com/doc/1O80-Iris.html |
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iris
iris species of crystal XIV; rainbow XV; flat circular coloured membrane in the aqueous humour of the eye; genus of tuberous or bulbous plants XVI. — L. īris — Gr. īris rainbow, coloured circle, etc., iris (plant), (I-) female messenger of the gods, whose sign was a rainbow.
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T. F. HOAD. "iris." The Concise Oxford Dictionary of English Etymology. 1996. Encyclopedia.com. 11 Feb. 2012 <http://www.encyclopedia.com>. T. F. HOAD. "iris." The Concise Oxford Dictionary of English Etymology. 1996. Encyclopedia.com. (February 11, 2012). http://www.encyclopedia.com/doc/1O27-iris.html T. F. HOAD. "iris." The Concise Oxford Dictionary of English Etymology. 1996. Retrieved February 11, 2012 from Encyclopedia.com: http://www.encyclopedia.com/doc/1O27-iris.html |
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iris
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"iris." World Encyclopedia. 2005. Encyclopedia.com. 11 Feb. 2012 <http://www.encyclopedia.com>. "iris." World Encyclopedia. 2005. Encyclopedia.com. (February 11, 2012). http://www.encyclopedia.com/doc/1O142-iris.html "iris." World Encyclopedia. 2005. Retrieved February 11, 2012 from Encyclopedia.com: http://www.encyclopedia.com/doc/1O142-iris.html |
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Iris
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MICHAEL KENNEDY and JOYCE BOURNE. "Iris." The Concise Oxford Dictionary of Music. 1996. Encyclopedia.com. 11 Feb. 2012 <http://www.encyclopedia.com>. MICHAEL KENNEDY and JOYCE BOURNE. "Iris." The Concise Oxford Dictionary of Music. 1996. Encyclopedia.com. (February 11, 2012). http://www.encyclopedia.com/doc/1O76-Iris.html MICHAEL KENNEDY and JOYCE BOURNE. "Iris." The Concise Oxford Dictionary of Music. 1996. Retrieved February 11, 2012 from Encyclopedia.com: http://www.encyclopedia.com/doc/1O76-Iris.html |
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Iris
Iris river: see Yeşil Irmak . |
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"Iris." The Columbia Encyclopedia, 6th ed.. 2008. Encyclopedia.com. 11 Feb. 2012 <http://www.encyclopedia.com>. "Iris." The Columbia Encyclopedia, 6th ed.. 2008. Encyclopedia.com. (February 11, 2012). http://www.encyclopedia.com/doc/1E1-X-IrisRiv.html "Iris." The Columbia Encyclopedia, 6th ed.. 2008. Retrieved February 11, 2012 from Encyclopedia.com: http://www.encyclopedia.com/doc/1E1-X-IrisRiv.html |
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Iris
Iris ♀ Greek. .
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PATRICK HANKS, KATE HARDCASTLE, and FLAVIA HODGES. "Iris." A Dictionary of First Names. 2006. Encyclopedia.com. 11 Feb. 2012 <http://www.encyclopedia.com>. PATRICK HANKS, KATE HARDCASTLE, and FLAVIA HODGES. "Iris." A Dictionary of First Names. 2006. Encyclopedia.com. (February 11, 2012). http://www.encyclopedia.com/doc/1O41-Iris.html PATRICK HANKS, KATE HARDCASTLE, and FLAVIA HODGES. "Iris." A Dictionary of First Names. 2006. Retrieved February 11, 2012 from Encyclopedia.com: http://www.encyclopedia.com/doc/1O41-Iris.html |
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iris
iris see eye . |
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Cite this article
"iris." The Columbia Encyclopedia, 6th ed.. 2008. Encyclopedia.com. 11 Feb. 2012 <http://www.encyclopedia.com>. "iris." The Columbia Encyclopedia, 6th ed.. 2008. Encyclopedia.com. (February 11, 2012). http://www.encyclopedia.com/doc/1E1-X-iris-ey.html "iris." The Columbia Encyclopedia, 6th ed.. 2008. Retrieved February 11, 2012 from Encyclopedia.com: http://www.encyclopedia.com/doc/1E1-X-iris-ey.html |
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Iris
Iris (ˈaɪrɪs) infrared intruder system
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FRAN ALEXANDER , PETER BLAIR , JOHN DAINTITH , ALICE GRANDISON , VALERIE ILLINGWORTH , ELIZABETH MARTIN , ANNE STIBBS , JUDY PEARSALL , and SARA TULLOCH. "Iris." The Oxford Dictionary of Abbreviations. 1998. Encyclopedia.com. 11 Feb. 2012 <http://www.encyclopedia.com>. FRAN ALEXANDER , PETER BLAIR , JOHN DAINTITH , ALICE GRANDISON , VALERIE ILLINGWORTH , ELIZABETH MARTIN , ANNE STIBBS , JUDY PEARSALL , and SARA TULLOCH. "Iris." The Oxford Dictionary of Abbreviations. 1998. Encyclopedia.com. (February 11, 2012). http://www.encyclopedia.com/doc/1O25-Iris.html FRAN ALEXANDER , PETER BLAIR , JOHN DAINTITH , ALICE GRANDISON , VALERIE ILLINGWORTH , ELIZABETH MARTIN , ANNE STIBBS , JUDY PEARSALL , and SARA TULLOCH. "Iris." The Oxford Dictionary of Abbreviations. 1998. Retrieved February 11, 2012 from Encyclopedia.com: http://www.encyclopedia.com/doc/1O25-Iris.html |
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iris
iris •arris, Clarice, Harries, Harris, Paris
•mattress • actress • benefactress
•Polaris • enchantress
•derris, Nerys, terrace
•Emrys • empress
•directress, Electress
•temptress • sempstress
•Apollinaris, heiress
•waitress • seamstress • ex libris
•headmistress, mistress
•housemistress • toastmistress
•schoolmistress • ancestress
•dentifrice
•iris, Osiris
•tigress, Tigris
•cypress
•Boris, doch-an-dorris, Doris, Horace, Maurice, Norris, orris
•cantoris, Dolores, loris
•laundress • fortress • jointress
•hubris • buttress
•conductress, instructress, seductress
•huntress • peeress • Beatrice
•arbitress • berberis • anchoress
•ephemeris • ambassadress
•adventuress • clitoris • authoress
•avarice
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"iris." Oxford Dictionary of Rhymes. 2007. Encyclopedia.com. 11 Feb. 2012 <http://www.encyclopedia.com>. "iris." Oxford Dictionary of Rhymes. 2007. Encyclopedia.com. (February 11, 2012). http://www.encyclopedia.com/doc/1O233-iris.html "iris." Oxford Dictionary of Rhymes. 2007. Retrieved February 11, 2012 from Encyclopedia.com: http://www.encyclopedia.com/doc/1O233-iris.html |
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