tetrahedron
Definitions
A polyhedron with four triangular faces.
A solid figure having four faces, especially one that is a regular triangular pyramid.
Examples
A tetrahedron is a polyhedron composed of four triangular faces.
The molecular structure of methane is shaped like a perfect tetrahedron.
In geometry class, we calculated the surface area of a regular tetrahedron.
Synonyms
triangular pyramid triangular tetrahedron four-faced polyhedron simplex