Tantalic

from The Collaborative International Dictionary of English v.0.48

Tantalic \Tan*tal"ic\, a. (Chem.)
   Of or pertaining to tantalum; derived from, or containing,
   tantalum; specifically, designating any one of a series of
   acids analogous to nitric acid and the polyacid compounds of
   phosphorus.
   [1913 Webster]