icosahedron

American  

[ahy-koh-suh-hee-druhn, ahy-kos-uh-] / aɪˌkoʊ səˈhi drən, aɪˌkɒs ə- /

noun

plural

icosahedrons, icosahedra

1. a solid figure having 20 faces.

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icosahedron British  

/ ˌaɪkəsəˈhiːdrən /

noun

1. a solid figure having 20 faces. The faces of a regular icosahedron are equilateral triangles

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icosahedron Scientific  

/ ī-kō′sə-hē′drən /

plural

icosahedrons

1. A polyhedron having twenty faces.

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Other Word Forms

• icosahedral adjective

Etymology

Origin of icosahedron

1560–70; < Greek eikosáedron, equivalent to eikosa- (variant of eikosi-, combining form of eíkosi twenty) + -edron -hedron

Example Sentences

Continental Drift is Earth in miniature, mapped onto a truncated icosahedron — a soccer ball — with its regular patchwork of 12 pentagonal faces and 20 hexagonal faces.

From New York Times • Jan. 1, 2023

There, he can sit and admire it along with the rest of a collection that includes work from real artists, such as the 80-inch infinity light icosahedron sculpture by L.A.’s Anthony James.

From Seattle Times • Dec. 5, 2022

This was done by inscribing triangles on the surfaces of an icosahedron, an idea borrowed from Buckminster Fuller.

From Nature • Dec. 11, 2018

By how much does the surface area of an icosahedron increase as the side length of each triangle doubles from a unit to 2a units?

From Textbooks • Mar. 30, 2016

The third solid is a regular icosahedron, having twenty triangular equilateral bases, and therefore 120 rectangular scalene triangles.

From Timaeus by Jowett, Benjamin