The Collaborative International Dictionary of English v.0.48:

Daphnin \Daph"nin\, n. [Cf. F. daphnine.] (Chem.)
   (a) A dark green bitter resin extracted from the mezereon
       (Daphne mezereum) and regarded as the essential
       principle of the plant. [R.]
   (b) A white, crystalline, bitter substance, regarded as a
       glucoside, and extracted from Daphne mezereum and
       Daphne alpina.
       [1913 Webster]