icosahedron
/ˌʌɪkɒsəˈhiːdrən
/noun (plural icosahedra /ˌʌɪkɒsəˈhiːdrə/ or icosahedrons)
A solid figure with twenty plane faces, especially equilateral triangular ones.Four more Archimedeans appear in the Short book on the five regular solids: the truncated cube, the truncated octahedron, the truncated icosahedron and the truncated dodecahedron....
- One of Plato's perfect solids, the icosahedron has 20 triangular faces.
- Hypsicles relates that his father and Basilides studied a treatise by Apollonius on a dodecahedron and an icosahedron in the same sphere and decided that Apollonius's treatment was not satisfactory.
Derivatives
icosahedral
- You may note that the spheres sit more or less on the vertices of an icosahedron, which is why this configuration is called the icosahedral arrangement.
- Thus, the combination of a spherical quadratic boundary potential and icosahedral rotational symmetry conditions maintained the initial distribution of solvation waters at the exterior boundary.
- In order to simulate a calcium ion located on a symmetry axis under icosahedral boundary conditions, it was necessary to develop a single-atom model that conforms to the symmetry requirements.
Origin
Late 16th century: via late Latin from Greek eikosaedron, neuter (used as a noun) of eikosaedros 'twenty-faced'.