The Collaborative International Dictionary
Pyroboric
Pyroboric \Pyr`o*bo"ric\, a. [Pyro- + boric.] (Chem.) Pertaining to derived from, or designating, an acid, H2B4O7 (called also tetraboric acid), which is the acid ingredient of ordinary borax, and is obtained by heating boric acid.
Wiktionary
pyroboric
a. Of or relating to pyroboric acid or its derivatives.