Definition of tetrahedron
: a polyhedron that has four faces
Recent Examples of tetrahedron from the Web
The new metropolis would consist of a giant tetrahedron—a pyramid made of equilateral triangles—a shape that Fuller, the popularizer of the geodesic dome, admired for its stability and symmetry.
As Mars cooled internally and shrank, some faces of the martian tetrahedron slumped.
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Did You Know?
The simplest tetrahedron is made of four equal-sided triangles: one is used as the base, and the other three are fitted to it and each other to make a pyramid. But the great pyramids of Egypt aren't tetrahedrons: they instead have a square base and four triangular faces, and thus are five-sided rather than four-sided.
Origin and Etymology of tetrahedron
New Latin, from Late Greek tetraedron, neuter of tetraedros having four faces, from Greek tetra- + hedra seat, face — more at sit
First Known Use: 1570
Learn More about tetrahedron
Britannica.com: Encyclopedia article about tetrahedron
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