The Collaborative International Dictionary of English v.0.48:

Crystal \Crys"tal\ (kr[i^]s"tal), n. [OE. cristal, F. cristal,
   L. crystallum crystal, ice, fr. Gr. kry`stallos, fr. kry`os
   icy cold, frost; cf. AS. crystalla, fr. L. crystallum; prob.
   akin to E. crust. See Crust, Raw.]
   1. (Chem. & Min.) The regular form which a substance tends to
      assume in solidifying, through the inherent power of
      cohesive attraction. It is bounded by plane surfaces,
      symmetrically arranged, and each species of crystal has
      fixed axial ratios. See Crystallization.
      [1913 Webster]

   2. The material of quartz, in crystallization transparent or
      nearly so, and either colorless or slightly tinged with
      gray, or the like; -- called also rock crystal.
      Ornamental vessels are made of it. Cf. Smoky quartz,
      Pebble; also Brazilian pebble, under Brazilian.
      [1913 Webster]

   3. A species of glass, more perfect in its composition and
      manufacture than common glass, and often cut into
      ornamental forms. See Flint glass.
      [1913 Webster]

   4. The glass over the dial of a watch case.
      [1913 Webster]

   5. Anything resembling crystal, as clear water, etc.
      [1913 Webster]

            The blue crystal of the seas.         --Byron.
      [1913 Webster]

   Blood crystal. See under Blood.

   Compound crystal. See under Compound.

   Iceland crystal, a transparent variety of calcite, or
      crystallized calcium carbonate, brought from Iceland, and
      used in certain optical instruments, as the polariscope.


   Rock crystal, or Mountain crystal, any transparent
      crystal of quartz, particularly of limpid or colorless
      quartz.
      [1913 Webster]

The Collaborative International Dictionary of English v.0.48:

Crystal \Crys"tal\, a.
   Consisting of, or like, crystal; clear; transparent; lucid;
   pellucid; crystalline.
   [1913 Webster]

         Through crystal walls each little mote will peep.
                                                  --Shak.
   [1913 Webster]

         By crystal streams that murmur through the meads.
                                                  --Dryden.
   [1913 Webster]

         The crystal pellets at the touch congeal,
         And from the ground rebounds the ratting hail. --H.
                                                  Brooks.
   [1913 Webster]

The Free On-line Dictionary of Computing (17 December 2009):

Crystal

   Concurrent Representation of Your Space-Time ALgorithms.

   A recursion equation parallel language.

   ["A Parallel Language and its Compilation to Multiprocessor
   Machines or VLSI", M.C. Chen, 13th POPL, ACM 1986 pp.131-139].

   (1994-12-06)


Easton's 1897 Bible Dictionary:

Crystal
(Ezek. 1:22, with the epithet "terrible," as dazzling the
spectators with its brightness). The word occurs in Rev. 4:6;
21:11; 22:1. It is a stone of the flint order, the most refined
kind of quartz. The Greek word here used means also literally
"ice." The ancients regarded the crystal as only pure water
congealed into extreme hardness by great length of time.

U.S. Gazetteer (1990):

Crystal, MI
  Zip code(s): 48818
Crystal, MN (city, FIPS 14158)
  Location: 45.03730 N, 93.35935 W
  Population (1990): 23788 (9541 housing units)
  Area: 14.9 sq km (land), 0.2 sq km (water)
  Zip code(s): 55428
Crystal, ND (city, FIPS 17060)
  Location: 48.59845 N, 97.66836 W
  Population (1990): 199 (96 housing units)
  Area: 1.7 sq km (land), 0.0 sq km (water)
  Zip code(s): 58222

Moby Thesaurus II by Grady Ward, 1.0:

114 Moby Thesaurus words for "crystal":
   Benzedrine, Benzedrine pill, C, Dexamyl, Dexamyl pill, Dexedrine,
   Dexedrine pill, Methedrine, amphetamine, amphetamine sulfate,
   avalanche, blizzard, clear, clear as crystal, clear-cut, cocaine,
   coke, craggy, crystal-clear, crystalline,
   dextroamphetamine sulfate, diaphane, diaphanous, driven snow,
   filmy, flake, flurry, football, gauzy, gem, gem stone, gossamer,
   gossamery, granular snow, gravelly, gritty, heart, igloo,
   jolly bean, lapideous, light-pervious, limpid, lithoid, lithoidal,
   lucent, lucid, luminous, mantle of snow,
   methamphetamine hydrochloride, mogul, monolithic, nonopaque,
   pebbled, pebbly, peekaboo, pellucid, pep pill, porphyritic,
   precious stone, purple heart, revealing, rock-ribbed, rock-strewn,
   rock-studded, rocklike, rocky, sandy, see-through,
   semiprecious stone, sheer, shingled, shingly, slosh, slush, snow,
   snow banner, snow bed, snow blanket, snow blast, snow fence,
   snow flurry, snow roller, snow slush, snow squall, snow wreath,
   snow-crystal, snowball, snowbank, snowbridge, snowcap, snowdrift,
   snowfall, snowfield, snowflake, snowland, snowman, snowscape,
   snowshed, snowslide, snowslip, snowstorm, speed, stimulant, stone,
   stonelike, stony, thin, trachytic, translucent, transparent,
   transpicuous, unclouded, upper, wet snow