Source : Webster's Revised Unabridged Dictionary (1913)

Quercitrin \Quer"cit*rin\, n. [Cf. F. quercitrin. See
   {Quercitron}.] (Chem.)
   A glucoside extracted from the bark of the oak ({Quercus}) as
   a bitter citron-yellow crystalline substance, used as a
   pigment and called {quercitron}.