A pyramid with a heptagonal base. The heptagonal pyramid is one of the 257 convex octahedra.
Heptagonal Pyramid
See also
Heptagon, PyramidExplore with Wolfram|Alpha
Cite this as:
Weisstein, Eric W. "Heptagonal Pyramid." From MathWorld--A Wolfram Web Resource. https://mathworld.wolfram.com/HeptagonalPyramid.html