The Collaborative International Dictionary of English v.0.48:

Iris \I"ris\, n.; pl. E. Irises, L. Irides. [L. iris,
   iridis, the goddess, Gr. ?, ?, the rainbow, iris of the eye,
   the plant Iris. Cf. Orris.]
   1. (Class. Myth.) The goddess of the rainbow, and
      swift-footed messenger of the gods. --Shak.
      [1913 Webster]

   2. The rainbow. --Sir T. Browne.
      [1913 Webster]

   3. An appearance resembling the rainbow; a prismatic play of
      colors. --Tennyson.
      [1913 Webster]

   4. (Anat.) The contractile membrane perforated by the pupil,
      and forming the colored portion of the eye. See Eye.
      [1913 Webster]

   5. (Bot.) A genus of plants having showy flowers and bulbous
      or tuberous roots, of which the flower-de-luce
      (fleur-de-lis), orris, and other species of flag are
      examples. See Illust. of Flower-de-luce.
      [1913 Webster]

   6. (Her.) See Fleur-de-lis, 2.
      [1913 Webster]

   7. (Zool.) the inner circle of an oscillated color spot.
      [Webster 1913 Suppl.]

   8. same as iris diaphragm.
      [PJC]

WordNet (r) 3.0 (2006):

iris
    n 1: plants with sword-shaped leaves and erect stalks bearing
         bright-colored flowers composed of three petals and three
         drooping sepals [syn: iris, 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 [syn:
       iris, iris diaphragm]

Moby Thesaurus II by Grady Ward, 1.0:

98 Moby Thesaurus words for "iris":
   Dalmatian, antigorite, baby blues, band, banjo eyes, bar,
   bespangle, bespeckle, bespot, blotch, bright eyes, butterfly,
   candy cane, chameleon, check, checker, cheetah, chrysotile,
   clear eyes, confetti, cornea, crazy quilt, dapple, dot, eye,
   eyeball, eyelid, firedog, flake, fleck, freckle, goggle eyes,
   harlequin, iridesce, iridize, jaguar, lens, leopard, lid, mackerel,
   mackerel sky, maculate, marble, marbled paper, marbleize, moire,
   mother-of-pearl, motley, mottle, nacre, naked eye,
   nictitating membrane, ocelot, oculus, opal, opalesce, ophite,
   optic, optic nerve, orb, organ of vision, patchwork quilt, peacock,
   peeper, pepper, polychrome, polychromize, popeyes, pupil, rainbow,
   retina, saucer eyes, sclera, serpentine, serpentine marble,
   shot silk, spangle, speck, speckle, spectrum, splotch, spot,
   sprinkle, starry orbs, stigmatize, stipple, streak, striate,
   stripe, stud, tattoo, tessellate, tortoise shell, unaided eye,
   variegate, vein, visual organ, zebra



V.E.R.A. -- Virtual Entity of Relevant Acronyms (February 2016):

IRIS
       Institute for Robotics and Intelligent Systems (org., Canada)


V.E.R.A. -- Virtual Entity of Relevant Acronyms (February 2016):

IRIS
       Internet Registry Information Service (XML, Internet)


The Free On-line Dictionary of Computing (30 December 2018):

IRIS

    Institute for Research in Information and Scholarship
   of Brown University (Providence RI).

   (1994-11-04)


The Free On-line Dictionary of Computing (30 December 2018):

Iris

   An object-oriented DBMS.

   (1994-11-04)