tetrahedron

American  

[te-truh-hee-druhn] / ˌtɛ trəˈhi drən /

noun

plural

tetrahedrons, tetrahedra

1. Geometry. a solid contained by four plane faces; a triangular pyramid.

2. any of various objects resembling a tetrahedron in the distribution of its faces or apexes.

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tetrahedron British  

/ ˌtɛtrəˈhiːdrən /

noun

1. a solid figure having four plane faces. A regular tetrahedron has faces that are equilateral triangles See also polyhedron

2. any object shaped like a tetrahedron

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tetrahedron Scientific  

/ tĕt′rə-hē′drən /

plural

tetrahedrons

1. A polyhedron having four faces.

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Other Word Forms

• tetrahedral adjective
• tetrahedrally adverb

Etymology

Origin of tetrahedron

1560–70; tetra- + -hedron, modeled on Late Greek tetráedron, noun use of neuter of tetráedros four-sided

Example Sentences

Many elements overlapped, forming a multidimensional sculpture: a triangle might jut out of a tetrahedron and meet another triangle at a point.

From Scientific American • Sep. 26, 2022

For example, a tetrahedron, a solid three-dimensional pyramid with four triangular faces, would fill in a group of four neurons firing together.

From Scientific American • Sep. 26, 2022

Find the moments of inertia of the tetrahedron Q about the yz-plane, the xz-plane, and the xy-plane.

From Textbooks • Mar. 30, 2016

The building block of all of these minerals is the silica tetrahedron, a combination of four oxygen atoms and one silicon atom.

From Textbooks • Jan. 1, 2015

The probe was on the central panel of the unfolded tetrahedron.

From "The Martian" by Andy Weir