The Collaborative International Dictionary of English v.0.48:

Tetanin \Tet"a*nin\, n. (Physiol. Chem.)
   A poisonous base (ptomaine) formed in meat broth through the
   agency of a peculiar microbe from the wound of a person who
   has died of tetanus; -- so called because it produces tetanus
   as one of its prominent effects.
   [1913 Webster]