The Collaborative International Dictionary of English v.0.48:

Cauterant \Cau"ter*ant\, n.
   A cauterizing substance.
   [1913 Webster]

WordNet (r) 3.0 (2006):

cauterant
    n 1: an instrument or substance used to destroy tissue for
         medical reasons (eg removal of a wart) by burning it with a
         hot iron or an electric current or a caustic or by freezing
         it [syn: cautery, cauterant]

Moby Thesaurus II by Grady Ward, 1.0:

25 Moby Thesaurus words for "cauterant":
   acid, actual cautery, brand, brand iron, branding iron, burning,
   calefacient, calefactive, calefactory, caustic, cauter, cauterizer,
   cautery, chafing, corrosive, electrocautery, escharotic, heating,
   hot iron, lunar caustic, mordant, moxa, potential cautery, radium,
   warming