n., pl., i·ris·es, or i·ri·des (ī'rĭ-dēz', ĭr'ĭ-).
- 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.
- Any of numerous plants of the genus Iris, having narrow sword-shaped leaves and showy, variously colored flowers.
- A rainbow or rainbowlike display of colors.
- An iris diaphragm.
[Middle English, iris (the plant), from Latin īris, īrid-, rainbow, iris (the plant), from Greek, rainbow, brightly-colored gemstone, iris of the eye.]
The American Heritage® Dictionary of the English Language, Fourth Edition Copyright © 2007, 2000 by Houghton Mifflin Company. Updated in 2009. Published by Houghton Mifflin Company. All rights reserved.
