The Collaborative International Dictionary of English v.0.48:

Viperine \Vi"per*ine\ (?; 277), a. [L. viperinus: cf. F.
   vip['e]rin.]
   Of or pertaining to a viper or vipers; resembling a viper.
   [1913 Webster]

   Viperine snake. (Zool.)
   (a) Any venomous snake of the family Viperidae.
   (b) A harmless snake resembling a viper in form or color,
       esp. Tropidonotus viperinus, a small European species
       which resembles the viper in color.
       [1913 Webster]