iris

Definitions

• (botany) A plant of the genus Iris, common in the northern hemisphere, and generally having attractive blooms (See ).
• (anatomy) 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 (See ).
• (photography) A diaphragm used to regulate the size of a hole, especially as a way of controlling the amount of light reaching a lens.
• (poetic) A rainbow, or other colourful refraction of light.
• (electronics) A constricted opening in the path inside a waveguide, used to form a resonator.
• (zoology) The inner circle of an oscillated color spot.