ico·​sa·​he·​dron | \ (ˌ)ī-ˌkō-sə-ˈhē-drən How to pronounce icosahedron (audio) , -ˌkä-\
plural icosahedrons or icosahedra\ (ˌ)ī-​ˌkō-​sə-​ˈhē-​drə How to pronounce icosahedra (audio) , -​ˌkä-​ \

Definition of icosahedron

: a polyhedron having 20 faces

Examples of icosahedron in a Sentence

Recent Examples on the Web

For that kind of math, the icosahedron was the ideal random number generator. William Herkewitz, Popular Mechanics, "Why D&D Modernized Its Magic for a New Generation of Fantasy," 1 Sep. 2019 The Florence specimen exhibited the symmetries of an icosahedron, a soccer-ball-like atomic arrangement that can be viewed from 60 different angles without any change to the structure’s overall orientation. Quanta Magazine, "In a Grain, a Glimpse of the Cosmos," 13 June 2014 The immersive experience took place under a giant version of their icosahedron logo, which — Odesza explained in a Reddit thread — represents their genre and style versatility. Susie Schmank, Indianapolis Star, "Odesza sets the bar high for White River concert season, despite chilly conditions," 30 Apr. 2018 They are defined by symmetry, and the Greeks knew that there were only five possibilities meeting the criteria: the tetrahedron, cube, octahedron, dodecahedron and icosahedron. Eugenia Cheng, WSJ, "Lessons of the Möbius Bagel," 10 Aug. 2017 The icosahedron is made from 20 identical equilateral triangles and seemed to exist nowhere except in mathematicians’ imaginations. Eugenia Cheng, WSJ, "Lessons of the Möbius Bagel," 10 Aug. 2017

These example sentences are selected automatically from various online news sources to reflect current usage of the word 'icosahedron.' Views expressed in the examples do not represent the opinion of Merriam-Webster or its editors. Send us feedback.

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First Known Use of icosahedron

1570, in the meaning defined above

History and Etymology for icosahedron

Greek eikosaedron, from eikosi twenty + -edron -hedron — more at vigesimal

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Statistics for icosahedron

Last Updated

30 Sep 2019

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Time Traveler for icosahedron

The first known use of icosahedron was in 1570

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More from Merriam-Webster on icosahedron

Britannica English: Translation of icosahedron for Arabic Speakers

Britannica.com: Encyclopedia article about icosahedron

Comments on icosahedron

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a topic to which one constantly reverts

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