The Collaborative International Dictionary of English v.0.48:

Transparent \Trans*par"ent\, a. [F., from LL. transparens,
   -entis, p. pr. of transparere to be transparent; L. trans
   across, through + parere to appear. See Appear.]
   1. Having the property of transmitting rays of light, so that
      bodies can be distinctly seen through; pervious to light;
      diaphanous; pellucid; as, transparent glass; a transparent
      diamond; -- opposed to opaque. "Transparent elemental
      air." --Milton.
      [1913 Webster]

   2. Admitting the passage of light; open; porous; as, a
      transparent veil. --Dryden.
      [1913 Webster]

   Syn: Translucent; pellucid; clear; bright; limpid; lucid;
        diaphanous. See Translucent.
        [1913 Webster] -- Trans*par"ent*ly, adv. --
        Trans*par"ent*ness, n.
        [1913 Webster]

WordNet (r) 3.0 (2006):

transparentness
    n 1: the quality of being clear and transparent [syn:
         transparency, transparence, transparentness]