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Related to icosahedra: Icosahedral symmetry
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 (ī-kō′sə-hē′drən, ī-kŏs′ə-)
n. pl. i·co·sa·he·drons or i·co·sa·he·dra (-drə)
A polyhedron having 20 faces.

[Greek eikosaedron, from neuter of Greek eikosaedros, twenty-sided : eikosi, twenty; see wīkm̥tī- in Indo-European roots + -edros, -sided; see -hedron.]

i·co′sa·he′dral (-drəl) adj.


n, pl -drons or -dra (-drə)
(Mathematics) a solid figure having 20 faces. The faces of a regular icosahedron are equilateral triangles
[C16: from Greek eikosaedron, from eikosi twenty + -edron -hedron]
ˌicosaˈhedral adj


(aɪˌkoʊ səˈhi drən, aɪˌkɒs ə-)

n., pl. -drons, -dra (-drə).
a solid figure having 20 faces.
[1560–70; < Greek eikosáedron=eikosa-, variant of eikosi-, comb. form of eíkosi twenty + -edron -hedron]
ThesaurusAntonymsRelated WordsSynonymsLegend:
Noun1.icosahedron - any polyhedron having twenty plane facesicosahedron - any polyhedron having twenty plane faces
polyhedron - a solid figure bounded by plane polygons or faces
References in periodicals archive ?
Icosahedra are symmetrical about their centers allowing full range attachment of the virus particle to a host cell without regard to virion orientation.
Contrast Nixon's obliviousness with the detailed account of Leonardo's latest invention, something called a due rote: "You turned the pedals with your feet, which turned the big cog wheel, which pulled the chain forward, cog by cog, causing the smaller wheel to turn the hind rota, thereby propelling the whole machine forward" (4); or compare it to Leonardo's joy at what the morning light does to his studio's clutter: "Meadow grass from Fiesole, icosahedra, cogs, gears, plaster, maps, lutes, brushes, an adze, magic squares, pigments, a Roman head Brunelleschi and Donatello brought him from their excavations, the skeleton of a bird: how beautifully the Tuscan light gave him his things again every morning, even if the kite had been in his sleep" (3).
Regular icosahedra and dodecahedra are special forms of both icosahedral point groups, 235 and m35.