'Tetradymite' definitions:

Definition of 'Tetradymite'

From: GCIDE
  • Tetradymite \Tet*rad"y*mite\, n. [Gr. tetra`dymos fourfold. So named from its occurrence in compound twin crystals, or fourlings.] (Min.) A telluride of bismuth. It is of a pale steel-gray color and metallic luster, and usually occurs in foliated masses. Called also telluric bismuth. [1913 Webster]