From Longman Dictionary of Contemporary Englishirisi‧ris /ˈaɪərɪs $ ˈaɪrɪs/ noun [countable] 1 HBPDLGa tall plant with long thin leaves and large purple, yellow, or white flowers2 
HBthe round coloured part of your eye, that surrounds the black pupil
HBthe round coloured part of your eye, that surrounds the black pupilExamples from the Corpus
iris• I have been in my house like an iris in an eye with the eyelid shut.• An all-white spring garden of azaleas, tulips and iris can be soothing.• Being a bearded iris, I. pallida needs full light and dryish, or at least free-draining soil.• With a circular iris, the focus is maintained in both dimensions of the field of view.• The marble iris stood peacefully on a low shelf.• A useful group of iris with clumps of grassy foliage.• But it can be made to bulge and glitter with a maestro behind the iris.Origin iris (1400-1500) Latin Greek, “rainbow, iris plant, iris of the eye” 