It could be an octagonal based pyramid
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Faces=9 Vertices: 9 Edges=16
It has 8 vertices, 12 edges and 6 faces.
A pyramid with an n-sided base will have n + 1 vertices, n + 1 faces, and 2n edges. 16 edges, 9 vertices
A decahedron is a polyhedron with 10 faces. There are several versions of a decahedron, but none of these are regular. By definition, they all have 10 faces. There is the octagonal prism - with 24 edges and 16 vertices, the square anti-prism, with 16 edges and 8 vertices, the square cupola, with 20 edges and 12 vertices, the pentagonal bi-pyramid, with 15 edges and 7 vertices and the augmented pentagonal prism, with 19 edges and 11 vertices. See, for example, http://en.wikipedia.org/wiki/Decahedron
An octagonal pyramid.