What does polyhedra mean?
Polyhedra is the plural of polyhedron, a term for three-dimensional geometric solids whose surfaces are made up of flat polygonal faces. The faces meet along straight edges and at vertices, and the shapes may be convex or non-convex, regular or irregular. Familiar examples include cubes, pyramids, prisms, and tetrahedra, although the word most often appears in mathematical, architectural, and design contexts. A cube, for instance, is a regular convex polyhedron with six square faces. The word comes from Greek roots meaning “many” and “seat” or “base,” reflecting the joining of multiple faces into a solid structure. Polyhedra is especially important in geometry, crystallography, computer graphics, and structural engineering, where they provide useful models for both ideal forms and real-world objects. When referring to one such solid, use the singular polyhedron.
plural nounPolyhedra is the plural form of polyhedron, referring to three-dimensional solid figures whose surfaces consist of flat polygonal faces. Each face is bounded by straight edges, and the faces meet at vertices.
- Three-dimensional solid figures with flat polygonal faces, straight edges, and vertices where the faces meet.
"The architect designed a complex structure from interlocking polyhedra."
"Regular polyhedra have been studied since ancient Greek mathematics."
"The software models the building as a collection of irregular polyhedra."
The usual plural of polyhedron; polyhedrons is also accepted.
"The five regular convex polyhedra are known as the Platonic solids."
A cube is one of the five regular convex polyhedra, the elegant geometric solids known as the Platonic solids.
Reviewed by Deb Chak, Editor. AI-assisted content curated by RJS Tech Solutions LLP.
Where does polyhedra come from?
The singular polyhedron comes from Greek polu-, meaning “many,” and hedra, meaning “seat,” “base,” or “face.” The term was borrowed into English through Latin, with the modern plural polyhedra formed by adding the Latin plural ending -a. Related mathematical terms include polygon, from the same “many” root, and tetrahedron and hexahedron, which share the “face” element.
Related word forms
How polyhedra is actually used
The usual plural is polyhedra. The plural polyhedrons is also accepted, but polyhedra is more common in technical and mathematical writing.
Easily confused with polyhedra
Polyhedron is the singular form, while polyhedra is the usual plural.
A polygon is a two-dimensional plane figure, whereas a polyhedron is a three-dimensional solid made from polygonal faces.