Definition of Iris

Noun: iris (irises,irides) I-ris

Plants with sword-shaped leaves and erect stalks bearing bright-coloured flowers composed of three petals and three drooping sepals
- flag, fleur-de-lis, sword lily
Muscular diaphragm that controls the size of the pupil which in turn controls the amount of light that enters the eye; it forms the coloured portion of the eye
Diaphragm consisting of thin overlapping plates that can be adjusted to change the diameter of a central opening
- iris diaphragm