'niobic acid' definitions:

Definition of 'niobic acid'

From: GCIDE

Columbic \Co*lum"bic\, a. [From Columbium.] (Chem.) Pertaining to, or containing, columbium or niobium; niobic. [1913 Webster]
Columbic acid (Chem.), a weak acid derived from columbic or niobic oxide, Nb2O5; -- called also niobic acid. [1913 Webster]