icosahedron

[ahy-koh-suh-hee-druhn, ahy-kos-uh-]

noun

plural

icosahedrons, icosahedra 

1. a solid figure having 20 faces.

icosahedron

/ ˌaɪkəsəˈhiːdrən /

noun

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

icosahedron

plural

icosahedrons 

1. A polyhedron having twenty faces.

Other Word Forms

• icosahedral adjective

Word History and Origins

Origin of icosahedron¹

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

Word History and Origins

Origin of icosahedron¹

C16: from Greek eikosaedron, from eikosi twenty + -edron _-hedron

Example Sentences

They are the dominant culture — and filmgoers who have never clutched a 20-sided icosahedron are subject to their throw of the dice.

Read more on New York Times

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.

Read more on New York Times

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.

Read more on Seattle Times

Many researchers initially questioned Shechtman’s findings, because it is mathematically impossible to fill space using only icosahedrons.

Read more on Scientific American

More precisely, the structure is about 0.7 nanometres across and is a truncated icosahedron — a polyhedron that has 12 pentagonal and 20 hexagonal faces.

Read more on Nature