Although, in theory, there are an infinite number of deltahedra, only eight of them are convex, including the regular tetrahedron, regular octahedron, snub disphenoid and regular icosahedron.
Deltohedra, not to be confused with deltahedra, are polyhedra whose faces are kites.
Examples
Several common deltahedra are shown here:
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| Regular tetrahedron | Regular octahedron | Snub disphenoid | Regular icosahedron |