a light, domelike structure developed by R. Buckminster Fuller to combine the properties of the tetrahedron and the sphere and consisting essentially of a grid of compression or tension members lying upon or parallel to great circles running in three directions in any given area, the typical form being the projection upon a sphere of an icosahedron, the triangular faces of which are filled with a symmetrical triangular, hexagonal, or quadrangular grid.
[ 1955-60 ]