A collection of faces of an -dimensional polytope or simplicial complex, one of each dimension 0, 1, ..., , which all have a common nonempty intersection. In normal three dimensions, the flag consists of a half-plane, its bounding ray, and the ray's endpoint.
Flag
See also
Flag Manifold, Vector Space FlagExplore with Wolfram|Alpha
Cite this as:
Weisstein, Eric W. "Flag." From MathWorld--A Wolfram Web Resource. https://mathworld.wolfram.com/Flag.html