The Collaborative International Dictionary of English v.0.48:

Bilin \Bi"lin\, n. [Cf. F. biline, from L. bilis bile.]
   (Physiol. Chem.)
   A name applied to the amorphous or crystalline mass obtained
   from bile by the action of alcohol and ether. It is composed
   of a mixture of the sodium salts of the bile acids.
   [1913 Webster]