follow Dictionary.com

Why is the ninth month called September?

iris

[ahy-ris] /ˈaɪ rɪs/
noun, plural irises, irides
[ir-i-deez, ahy-ri-] /ˈɪr ɪˌdiz, ˈaɪ rɪ-/ (Show IPA)
1.
Anatomy. the contractile, circular diaphragm forming the colored portion of the eye and containing a circular opening, the pupil, in its center.
2.
Botany. any plant of the genus Iris, having showy flowers and sword-shaped leaves.
Compare iris family.
3.
a flower of this plant.
4.
(initial capital letter) Classical Mythology. a messenger of the gods, regarded as the goddess of the rainbow.
5.
a rainbow.
6.
any appearance resembling a rainbow.
7.
Movies, Television. an iris-in or iris-out.
8.
Optics, Photography, iris diaphragm.
verb (used without object)
9.
Movies. to begin or end a take or scene with an iris-in or iris-out, achieved by manipulation of an iris diaphragm on the camera or by editing the film.
Origin
1350-1400
1350-1400; Middle English < Latin Īris, īris < Greek Îris, îris rainbow, goddess of the rainbow, halo, iris flower or root, iridescent crystal; in some senses < Neo-Latin < Greek: diaphragm of eye
Dictionary.com Unabridged
Based on the Random House Dictionary, © Random House, Inc. 2014.
Cite This Source
British Dictionary definitions for irisses

iris

/ˈaɪrɪs/
noun (pl) irises, irides (ˈaɪrɪˌdiːz; ˈɪrɪ-)
1.
the coloured muscular diaphragm that surrounds and controls the size of the pupil
2.
Also called fleur-de-lys. any plant of the iridaceous genus Iris, having brightly coloured flowers composed of three petals and three drooping sepals See also flag3 , orris1 , stinking iris
3.
Also called rainbow quartz. a form of quartz that reflects light polychromatically from internal fractures
4.
a rare or poetic word for rainbow
5.
something resembling a rainbow; iridescence
6.
short for iris diaphragm
Word Origin
C14: from Latin: rainbow, iris (flower), crystal, from Greek

Iris

/ˈaɪrɪs/
noun
1.
the goddess of the rainbow along which she travelled to earth as a messenger of the gods
Collins English Dictionary - Complete & Unabridged 2012 Digital Edition
© William Collins Sons & Co. Ltd. 1979, 1986 © HarperCollins
Publishers 1998, 2000, 2003, 2005, 2006, 2007, 2009, 2012
Cite This Source
Word Origin and History for irisses

iris

n.

late 14c., flowering plant (Iris germanica), also "prismatic rock crystal," from Latin iris (plural irides) "iris of the eye, iris plant, rainbow," from Greek iris (genitive iridos) "a rainbow; the lily; iris of the eye," originally "messenger of the gods," personified as the rainbow. The eye region was so called (early 15c. in English) for being the colored part; the Greek word was used of any brightly colored circle, "as that round the eyes of a peacock's tail" [Liddell and Scott].

Online Etymology Dictionary, © 2010 Douglas Harper
Cite This Source
irisses in Medicine

iris i·ris (ī'rĭs)
n. pl. i·ris·es or i·ri·des (ī'rĭ-dēz', ĭr'ĭ-)
The round pigmented contractile membrane of the eye that is perforated in the center by the pupil, forms the front part of the vascular tunic, and is attached on the margin to the ciliary body.


i'ri·dal (ī'rĭ-dl, ĭr'ĭ-) or i·rid'i·al (ī-rĭd'ē-əl, ĭ-rĭd'-) or i·rid'i·an adj.
The American Heritage® Stedman's Medical Dictionary
Copyright © 2002, 2001, 1995 by Houghton Mifflin Company. Published by Houghton Mifflin Company.
Cite This Source
irisses in Science
iris
  (ī'rĭs)   
Plural irises or irides (ī'rĭ-dēz', ĭr'ĭ-)
The colored, muscular ring around the pupil of the eye in vertebrate animals, located between the cornea and lens. Contraction and expansion of the iris controls the size of the pupil, thereby regulating the amount of light reaching the retina.
The American Heritage® Science Dictionary
Copyright © 2002. Published by Houghton Mifflin. All rights reserved.
Cite This Source
irisses in Culture
iris [(eye-ris)]

The colored membrane of the eye, surrounding the pupil, which by contracting and expanding regulates the amount of light that enters the eye.

The American Heritage® New Dictionary of Cultural Literacy, Third Edition
Copyright © 2005 by Houghton Mifflin Company.
Published by Houghton Mifflin Company. All rights reserved.
Cite This Source
Related Abbreviations for irisses

IRIS

Integrated Risk Information System
The American Heritage® Abbreviations Dictionary, Third Edition
Copyright © 2005 by Houghton Mifflin Company.
Published by Houghton Mifflin Company. All rights reserved.
Cite This Source
Encyclopedia Article for irisses

Iris

in Greek mythology, the personification of the rainbow and (in Homer's Iliad, for example) a messenger of the gods. According to the Greek poet Hesiod, she was the daughter of Thaumas and the ocean nymph Electra. In Hesiod's works, at least, she had the additional duty of carrying water from the River Styx in a ewer whenever the gods had to take a solemn oath. The water would render unconscious for one year any god or goddess who lied. In art, Iris was normally portrayed with wings, and her attributes were the herald's staff and a vase. She was shown serving wine to the gods or escorting them to the wedding of Peleus and Thetis.

Learn more about Iris with a free trial on Britannica.com

iris

in anatomy, the pigmented muscular curtain near the front of the eye, between the cornea and the lens, that is perforated by an opening called the pupil. The iris is located in front of the lens and ciliary body and behind the cornea. It is bathed in front and behind by a fluid known as the aqueous humour. The iris consists of two sheets of smooth muscle with contrary actions: dilation (expansion) and contraction (constriction). These muscles control the size of the pupil and thus determine how much light reaches the sensory tissue of the retina. The sphincter muscle of the iris is a circular muscle that constricts the pupil in bright light, whereas the dilator muscle of the iris expands the opening when it contracts. The amount of pigment contained in the iris determines eye colour. When there is very little pigment, the eye appears blue. With increased pigment, the shade becomes deep brown to black. Inflammation of the iris is termed iritis or anterior uveitis, a condition that commonly has no determinable cause. As a result of inflammation, the iris sticks to the lens or the cornea, blocking the normal flow of fluid in the eye. Complications of iritis include secondary glaucoma and blindness; treatment usually involves topical steroid eyedrops.

Learn more about iris with a free trial on Britannica.com
Encyclopedia Britannica, 2008. Encyclopedia Britannica Online.
Cite This Source

Word of the Day

Difficulty index for iris

All English speakers likely know this word

Word Value for irisses

0
0
Scrabble Words With Friends