The Collaborative International Dictionary of English v.0.48:

Ivory \I"vo*ry\ ([imac]"v[-o]*r[y^]), n.; pl. Ivories. [OE.
   ivori, F. ivoire, fr. L. eboreus made of ivory, fr. ebur,
   eboris, ivory, cf. Skr. ibha elephant. Cf. Eburnean.]
   [1913 Webster]
   1. The hard, white, opaque, fine-grained substance
      constituting the tusks of the elephant. It is a variety of
      dentine, characterized by the minuteness and close
      arrangement of the tubes, as also by their double flexure.
      It is used in manufacturing articles of ornament or
      utility.
      [1913 Webster]

   Note: Ivory is the name commercially given not only to the
         substance constituting the tusks of the elephant, but
         also to that of the tusks of the hippopotamus and
         walrus, the hornlike tusk of the narwhal, etc.
         [1913 Webster]

   2. The tusks themselves of the elephant, etc.
      [1913 Webster]

   3. Any carving executed in ivory. --Mollett.
      [1913 Webster]

   4. pl. Teeth; as, to show one's ivories. [Slang]
      [1913 Webster]

   Ivory black. See under Black, n.

   Ivory gull (Zool.), a white Arctic gull (Larus eburneus).


   Ivory nut (Bot.), the nut of a species of palm, the
      Phytephas macroarpa, often as large as a hen's egg. When
      young the seed contains a fluid, which gradually hardness
      into a whitish, close-grained, albuminous substance,
      resembling the finest ivory in texture and color, whence
      it is called vegetable ivory. It is wrought into various
      articles, as buttons, chessmen, etc. The palm is found in
      New Grenada. A smaller kind is the fruit of the Phytephas
      microarpa. The nuts are known in commerce as Corosso
      nuts.

   Ivory palm (Bot.), the palm tree which produces ivory nuts.


   Ivory shell (Zool.), any species of Eburna, a genus of
      marine gastropod shells, having a smooth surface, usually
      white with red or brown spots.

   Vegetable ivory, the meat of the ivory nut. See Ivory nut
      (above).
      [1913 Webster] ivorybill

WordNet (r) 3.0 (2006):

ivory
    n 1: a hard smooth ivory colored dentine that makes up most of
         the tusks of elephants and walruses [syn: ivory, tusk]
    2: a shade of white the color of bleached bones [syn: bone,
       ivory, pearl, off-white]

Moby Thesaurus II by Grady Ward, 1.0:

53 Moby Thesaurus words for "ivory":
   alabaster, alabastrine, albescent, billiard table, bones,
   bowling alley, bowling green, chalk, cream, creamy, cubes, dice,
   driven snow, dun-white, eggshell, fair, flat, fleece, flour, foam,
   glass, glaucescent, glaucous, gray-white, ice, ivory-white, level,
   light, lily, lint-white, maggot, mahogany, marble, milk, off-white,
   pale, paper, pearl, pearly, pearly-white, plane, satin, sheet,
   silk, silver, slide, smooth, snow, swan, tennis court, velvet,
   whitish, whity



Easton's 1897 Bible Dictionary:

Ivory
   (Heb. pl. shenhabbim, the "tusks of elephants") was early used
   in decorations by the Egyptians, and a great trade in it was
   carried on by the Assyrians (Ezek. 27:6; Rev. 18:12). It was
   used by the Phoenicians to ornament the box-wood rowing-benches
   of their galleys, and Hiram's skilled workmen made Solomon's
   throne of ivory (1 Kings 10:18). It was brought by the caravans
   of Dedan (Isa. 21:13), and from the East Indies by the navy of
   Tarshish (1 Kings 10:22). Many specimens of ancient Egyptian and
   Assyrian ivory-work have been preserved. The word _habbim_ is
   derived from the Sanscrit _ibhas_, meaning "elephant," preceded
   by the Hebrew article (ha); and hence it is argued that Ophir,
   from which it and the other articles mentioned in 1 Kings 10:22
   were brought, was in India.