Source : Webster's Revised Unabridged Dictionary (1913)

Bryonin \Bry"o*nin\, n. (Chem.)
   A bitter principle obtained from the root of the bryony
   ({Bryonia alba} and {B. dioica}). It is a white, or slightly
   colored, substance, and is emetic and cathartic.

Source : WordNet®

Bryonia alba
     n : white-flowered vine having thick roots and bearing small
         black berries; Europe to Iran [syn: {white bryony}, {devil's
         turnip}]