iris meaning and definition

IRIS noun

Definition of iris (noun)

1. plants with sword-shaped leaves and erect stalks bearing bright-colored flowers composed of three petals and three drooping sepals
   • synonyms: flag, fleur-de-lis, sword lily
2. muscular diaphragm that controls the size of the pupil which in turn controls the amount of light that enters the eye; it forms the colored portion of the eye
3. diaphragm consisting of thin overlapping plates that can be adjusted to change the diameter of a central opening
   • synonyms: iris diaphragm