tetrahedron

noun tet·ra·he·dron \ ˌte-trə-ˈhē-drən \

Definition of tetrahedron

plural tetrahedrons or tetrahedra play \-drə\
:a polyhedron that has four faces

Recent Examples of tetrahedron from the Web

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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.

Illustration of tetrahedron

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


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