Source : Webster's Revised Unabridged Dictionary (1913)

Scammony \Scam"mo*ny\ (sk[a^]m"m[-o]*n[y^]), n. [F.
   scammon['e]e, L. scammonia, scammonea, Gr. skammwni`a.]
   1. (Bot.) A species of bindweed or Convolvulus ({C.
      Scammonia}).

   2. An inspissated sap obtained from the root of the
      {Convolvulus Scammonia}, of a blackish gray color, a
      nauseous smell like that of old cheese, and a somewhat
      acrid taste. It is used in medicine as a cathartic.

Source : WordNet®

Convolvulus scammonia
     n : twining plant of Asia Minor having cream to purple flowers
         and long thick roots yielding a cathartic resin [syn: {scammony}]