出典:Wiktionary
midsphere (複数形 midspheres)
出典:Wikipedia
出典:『Wikipedia』 (2011/04/11 20:50 UTC 版)
In geometry, the midsphere or intersphere of a polyhedron is a sphere which is tangent to every edge of the polyhedron. That is to say, it touches any given edge at exactly one point. Not every polyhedron has a midsphere, but for every polyhedron there is a combinatorially equivalent polyhedron, the canonical polyhedron, that does have a midsphere.