白蜡树; 秦皮
Fraxin \Frax"in\, n. [From {Fraxinus}.] (Chem.) A colorless crystalline substance, regarded as a glucoside, and found in the bark of the ash ({Fraxinus}) and along with esculin in the bark of the horse-chestnut. It shows a delicate fluorescence in alkaline solutions; -- called also {paviin}.