thumb|Octadecagonal (18-sided) Pyramid (geometry)|pyramid right|thumb|169px|3D model of 18-sided pyramid thumb|a 19-sided 3d object composed of 1 hexagonal face, 12 rectangular faces, 6 triangular facesthumb|Heptadecagonal (17-sided) Prism (geometry)|prism A enneadecahedron (or enneakaidecahedron) is a polyhedron with 19 faces. No enneadecahedron is regular; hence, the name is ambiguous.
thumb|Octadecagonal (18-sided) Pyramid (geometry)|pyramid right|thumb|169px|3D model of 18-sided pyramid thumb|a 19-sided 3d object composed of 1 hexagonal face, 12 rectangular faces, 6 triangular facesthumb|Heptadecagonal (17-sided) Prism (geometry)|prism A enneadecahedron (or enneakaidecahedron) is a polyhedron with 19 faces. No enneadecahedron is regular; hence, the name is ambiguous.
There are numerous topologically distinct forms of an enneadecahedron, for example the octadecagonal (18-sided) pyramid, or the heptadecagonal (17-sided) prism; the latter is the only convex enneadecahedron with all regular polygonal faces.
Discovered by embedding cosine similarity (sentence-transformers MiniLM, 384-dim).