I. ˈīrə̇s noun
( plural iris·es -rə̇sə̇z ; or iri·des ˈirəˌdēz, ˈīr-)
Etymology: Middle English, from Latin, from Greek (basic meaning: rainbow) — more at wire
1. : a prismatic crystal ; especially : a quartz that is iridescent because of internal cracks
2.
a. : rainbow
b. : a play of colors resembling a rainbow : a circle or arch of rainbow hues
3.
[New Latin, from Greek]
a. : the opaque muscular contractile diaphragm that is suspended in the aqueous humor in front of the lens of the eye, is perforated by the pupil and is continuous peripherally with the ciliary body, has a deeply pigmented posterior surface which excludes the entrance of light except through the pupil and a variously colored anterior surface in different individuals which determines the color of the eyes — see eye illustration
b.
(1) : iris diaphragm ; especially : one used on a motion-picture camera in fading pictures in or out
(2) : a masking device having a circular opening of which the diameter can be varied
II. noun
Etymology: New Latin, from Latin, iris, any of various plants of the family Iridaceae
1. capitalized : the type genus of the family Iridaceae comprising perennial herbaceous plants that develop from rhizomes or bulbs, have linear or sword-shaped mostly basal leaves, erect stalks on which the flowers are borne, and short-lived usually brightly colored flowers with the three inner perianth segments erect and the three outer spreading or drooping, and include many widely cultivated ornamentals
2. plural irises or iris also irides : any plant or flower of the genus Iris — see bearded iris , beardless iris ; dutch iris , english iris , german iris , japanese iris , spanish iris
3. or iris blue : a pale blue to pale purple — called also endive blue
III. transitive verb
( -ed/-ing/-es )
1. : to make iridescent : give the form or appearance of a rainbow to
spray irised above the falls
2. : to operate the iris of a motion-picture camera so as to fade (a picture) — used with in or out