The Collaborative International Dictionary of English v.0.48:

Indican \In"di*can\, n. [See Indigo.]
   [1913 Webster]
   1. (Chem.) A glucoside (C14H17NO6) obtained from woad
      (indigo plant, Isatis Tinctoria) and other plants (see
      indigo), as a yellow or light brown sirup. When purified
      it is obtained as spear-shaped crystals. It has a nauseous
      bitter taste. By the action of acids, enzymes, etc., it
      breaks down into sugar and indigo. It is the source of
      natural indigo. Chemically it is the 3-glucoside of
      indole, H-indol-3-yl-[beta]-D-glucopyranoside.
      [1913 Webster +PJC]

   2. (Physiol. Chem.) An indigo-forming substance, found in
      urine, and other animal fluids, and convertible into red
      and blue indigo (urrhodin and uroglaucin). Chemically, it
      is indoxyl sulphate of potash, C8H6NSO4K, and is derived
      from the indol formed in the alimentary canal. Called also
      uroxanthin.
      [1913 Webster]

The Collaborative International Dictionary of English v.0.48:

Uroxanthin \U`ro*xan"thin\, n. [1st uro- + xanthin.] (Physiol.
   Chem.)
   Same as Indican.
   [1913 Webster]