'Tetrahedron' definitions:
Definition of 'tetrahedron'
From: WordNet
noun
Any polyhedron having four plane faces
Definition of 'Tetrahedron'
From: GCIDE
- Tetrahedron \Tet`ra*he"dron\, n. [Tetra- + Gr. ? seat, base, fr. ? to sit.] (Geom.) A solid figure inclosed or bounded by four triangles. [1913 Webster]
- Note: In crystallography, the regular tetrahedron is regarded as the hemihedral form of the regular octahedron. [1913 Webster]
- Regular tetrahedron (Geom.), a solid bounded by four equal equilateral triangles; one of the five regular solids. [1913 Webster]