Te-tär'to-hē'dral, a.
a. [Gr. τέταρτος, fourth, and ἕδρα, base.] (Crystallog.) Having one fourth the number of planes requisite to complete symmetry.
a. [Gr. τέταρτος, fourth, and ἕδρα, base.] (Crystallog.) Having one fourth the number of planes requisite to complete symmetry.