List of regular polytopes and compounds


This page lists the regular polytopes and regular polytope compounds in Euclidean, spherical and hyperbolic spaces.
The Schläfli symbol describes every regular tessellation of an n-sphere, Euclidean and hyperbolic spaces. A Schläfli symbol describing an n-polytope equivalently describes a tessellation of an -sphere. In addition, the symmetry of a regular polytope or tessellation is expressed as a Coxeter group, which Coxeter expressed identically to the Schläfli symbol, except delimiting by square brackets, a notation that is called Coxeter notation. Another related symbol is the Coxeter-Dynkin diagram which represents a symmetry group with no rings, and the represents regular polytope or tessellation with a ring on the first node. For example, the cube has Schläfli symbol, and with its octahedral symmetry, or, it is represented by Coxeter diagram.
The regular polytopes are grouped by dimension and subgrouped by convex, nonconvex and infinite forms. Nonconvex forms use the same vertices as the convex forms, but have intersecting facets. Infinite forms tessellate a one-lower-dimensional Euclidean space.
Infinite forms can be extended to tessellate a hyperbolic space. Hyperbolic space is like normal space at a small scale, but parallel lines diverge at a distance. This allows vertex figures to have negative angle defects, like making a vertex with seven equilateral triangles and allowing it to lie flat. It cannot be done in a regular plane, but can be at the right scale of a hyperbolic plane.
A more general definition of regular polytopes which do not have simple Schläfli symbols includes regular skew polytopes and regular skew apeirotopes with nonplanar facets or vertex figures.

Overview

This table shows a summary of regular polytope counts by dimension.
There are no Euclidean regular star tessellations in any number of dimensions.

One dimension

A one-dimensional polytope or 1-polytope is a closed line segment, bounded by its two endpoints. A 1-polytope is regular by definition and is represented by Schläfli symbol, or a Coxeter diagram with a single ringed node,. Norman Johnson calls it a dion and gives it the Schläfli symbol.
Although trivial as a polytope, it appears as the edges of polygons and other higher dimensional polytopes. It is used in the definition of uniform prisms like Schläfli symbol ×, or Coxeter diagram as a Cartesian product of a line segment and a regular polygon.

Two dimensions (polygons)

The two-dimensional polytopes are called polygons. Regular polygons are equilateral and cyclic. A p-gonal regular polygon is represented by Schläfli symbol.
Usually only convex polygons are considered regular, but star polygons, like the pentagram, can also be considered regular. They use the same vertices as the convex forms, but connect in an alternate connectivity which passes around the circle more than once to be completed.
Star polygons should be called nonconvex rather than concave because the intersecting edges do not generate new vertices and all the vertices exist on a circle boundary.

Convex

The Schläfli symbol represents a regular p-gon.
NameTriangle
Square

Pentagon
HexagonHeptagonOctagon-
Schläfli-
SymmetryD3, D4, D5, D6, D7, D8, -
Coxeter-
Image-
NameNonagon
DecagonHendecagonDodecagonTridecagonTetradecagon-
Schläfli-
SymmetryD9, D10, D11, D12, D13, D14, -
Dynkin-
Image-
NamePentadecagonHexadecagonHeptadecagonOctadecagonEnneadecagonIcosagon...p-gon
Schläfli
SymmetryD15, D16, D17, D18, D19, D20, Dp,
Dynkin
Image-

Spherical

The regular digon can be considered to be a degenerate regular polygon. It can be realized non-degenerately in some non-Euclidean spaces, such as on the surface of a sphere or torus.
NameMonogonDigon
Schläfli symbol
SymmetryD1, D2,
Coxeter diagram or
Image

Stars

There exist infinitely many regular star polytopes in two dimensions, whose Schläfli symbols consist of rational numbers. They are called star polygons and share the same vertex arrangements of the convex regular polygons.
In general, for any natural number n, there are n-pointed star regular polygonal stars with Schläfli symbols for all m such that m < n/2 and m and n are coprime. Cases where m and n are not coprime are called [|compound polygons].

'




'

'




-

'


'



'


---

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'

--

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Star polygons that can only exist as spherical tilings, similarly to the monogon and digon, may exist, however these do not appear to have been studied in detail.
There also exist failed star polygons, such as the piangle, which do not cover the surface of a circle finitely many times.

Skew polygons

In 3-dimensional space, a regular skew polygon is called an antiprismatic polygon, with the vertex arrangement of an antiprism, and a subset of edges, zig-zagging between top and bottom polygons.
In 4-dimensions a regular skew polygon can have vertices on a Clifford torus and related by a Clifford displacement. Unlike antiprismatic skew polygons, skew polygons on double rotations can include an odd-number of sides.
They can be seen in the Petrie polygons of the convex regular 4-polytopes, seen as regular plane polygons in the perimeter of Coxeter plane projection:
PentagonOctagonDodecagonTriacontagon

5-cell

16-cell

24-cell

600-cell

Three dimensions (polyhedra)

In three dimensions, polytopes are called polyhedra:
A regular polyhedron with Schläfli symbol, Coxeter diagrams, has a regular face type, and regular vertex figure.
A vertex figure is a polygon, seen by connecting those vertices which are one edge away from a given vertex. For regular polyhedra, this vertex figure is always a regular polygon.
Existence of a regular polyhedron is constrained by an inequality, related to the vertex figure's angle defect:
By enumerating the permutations, we find five convex forms, four star forms and three plane tilings, all with polygons and limited to:,,,, and.
Beyond Euclidean space, there is an infinite set of regular hyperbolic tilings.

Convex

The convex regular polyhedra are called the 5 Platonic solids. The vertex figure is given with each vertex count. All these polyhedra have an Euler characteristic of 2.
NameSchläfli
Coxeter
Image
Image
Faces
EdgesVertices
SymmetryDual
Tetrahedron
4
64
Td

Hexahedron
Cube
6
128
Oh

Octahedron
Octahedron
8
126
Oh

Cube
Dodecahedron12
3020
Ih

Icosahedron
Icosahedron20
3012
Ih

Dodecahedron

Spherical

In spherical geometry, regular spherical polyhedra exist that would otherwise be degenerate as polytopes. These are the hosohedra and their dual dihedra. Coxeter calls these cases "improper" tessellations.
The first few cases are listed below.
NameSchläfli
Coxeter
diagram
Image
Faces
π/p
EdgesVertices
SymmetryDual
Digonal hosohedron2
π/2
22
π/2
D2h

Self
Trigonal hosohedron3
π/3
32
D3h

Trigonal dihedron
Square hosohedron4
π/4
42
D4h

Square dihedron
Pentagonal hosohedron5
π/5
52
D5h

Pentagonal dihedron
Hexagonal hosohedron6
π/6
62
D6h

Hexagonal dihedron

NameSchläfli
Coxeter
diagram
Image
Faces
EdgesVertices
SymmetryDual
Digonal dihedron2
π/2
22
π/2
D2h

Self
Trigonal dihedron2
33
π/3
D3h

Trigonal hosohedron
Square dihedron2
44
π/4
D4h

Square hosohedron
Pentagonal dihedron2
55
π/5
D5h

Pentagonal hosohedron
Hexagonal dihedron2
66
π/6
D6h

Hexagonal hosohedron

Star-dihedra and hosohedra and also exist for any star polygon.

Stars

The regular star polyhedra are called the Kepler–Poinsot polyhedra and there are four of them, based on the vertex arrangements of the dodecahedron and icosahedron :
As spherical tilings, these star forms overlap the sphere multiple times, called its density, being 3 or 7 for these forms. The tiling images show a single spherical polygon face in yellow.
NameImage
Image
Image
Stellation
diagram
Schläfli
and
Coxeter
Faces
EdgesVertices

verf.
χDensitySymmetryDual
Small stellated dodecahedron
12

3012

−63Ih

Great dodecahedron
Great dodecahedron
12

3012

−63Ih

Small stellated dodecahedron
Great stellated dodecahedron
12

3020

27Ih

Great icosahedron
Great icosahedron
20

3012

27Ih

Great stellated dodecahedron

There are infinitely many failed star polyhedra. These are also spherical tilings with star polygons in their Schläfli symbols, but they do not cover a sphere finitely many times. Some examples are,,,,,, and.

Skew polyhedra

are generalizations to the set of regular polyhedron which include the possibility of nonplanar vertex figures.
For 4-dimensional skew polyhedra, Coxeter offered a modified Schläfli symbol for these figures, with implying the vertex figure, m l-gons around a vertex, and n-gonal holes. Their vertex figures are skew polygons, zig-zagging between two planes.
The regular skew polyhedra, represented by, follow this equation:
Four of them can be seen in 4-dimensions as a subset of faces of four regular 4-polytopes, sharing the same vertex arrangement and edge arrangement:

Four dimensions

Regular 4-polytopes with Schläfli symbol have cells of type, faces of type, edge figures
, and vertex figures.
The existence of a regular 4-polytope is constrained by the existence of the regular polyhedra. A suggested name for 4-polytopes is "polychoron".
Each will exist in a space dependent upon this expression:
These constraints allow for 21 forms: 6 are convex, 10 are nonconvex, one is a Euclidean 3-space honeycomb, and 4 are hyperbolic honeycombs.
The Euler characteristic for convex 4-polytopes is zero:

Convex

The 6 convex regular 4-polytopes are shown in the table below. All these 4-polytopes have an Euler characteristic of 0.
Name
Schläfli
Coxeter
Cells
Faces
Edges
Vertices
Dual
5-cell
5
10
10
5
8-cell

8
24
32
16
16-cell
16-cell
16
32
24
8
Tesseract
24-cell24
96
96
24
120-cell120
720
1200
600
600-cell
600-cell600
1200
720
120
120-cell

Spherical

and hoso-4-topes exist as regular tessellations of the 3-sphere.
Regular di-4-topes include:,,,,,, and their hoso-4-tope duals :,,,,,. 4-polytopes of the form are the same as. There are also the cases which have dihedral cells and hosohedral vertex figures.
Schläfli
Coxeter
Cells
π/q
Faces
π/p,π/q
EdgesVerticesVertex figure
SymmetryDual
4
π/3
6
π/3,π/3
42
6
π/3
12
π/4,π/3
82
8
π/4
12
π/3,π/4
62
12
π/3
30
π/5,π/3
202
20
π/5
30
π/3,π/5
122

Stars

There are ten regular star 4-polytopes, which are called the Schläfli–Hess 4-polytopes. Their vertices are based on the convex 120-cell ' and 600-cell '.
Ludwig Schläfli found four of them and skipped the last six because he would not allow forms that failed the Euler characteristic on cells or vertex figures. Edmund Hess completed the full list of ten in his German book Einleitung in die Lehre von der Kugelteilung mit besonderer Berücksichtigung ihrer Anwendung auf die Theorie der Gleichflächigen und der gleicheckigen Polyeder .
There are 4 unique edge arrangements and 7 unique face arrangements from these 10 regular star 4-polytopes, shown as orthogonal projections:
Name
WireframeSolidSchläfli

Coxeter
Cells
Faces
Edges
Vertices
DensityχSymmetry groupDual
Icosahedral 120-cell

120
Icosahedron|
1200
Triangle|
720
Pentagram|
120
Great dodecahedron|
4480H4
Small stellated 120-cell
Small stellated 120-cell
120
Small stellated dodecahedron|
720
Pentagram|
1200
Triangle|
120
Dodecahedron|
4−480H4
Icosahedral 120-cell
Great 120-cell
120
Great dodecahedron|
720
Pentagon|
720
Pentagon|
120
Small stellated dodecahedron|
60H4
Self-dual
Grand 120-cell
120
Dodecahedron|
720
Pentagon|
720
Pentagram|
120
Great icosahedron|
200H4
Great stellated 120-cell
Great stellated 120-cell
120
Great stellated dodecahedron|
720
Pentagram|
720
Pentagon|
120
Icosahedron|
200H4
Grand 120-cell
Grand stellated 120-cell
120
Small stellated dodecahedron|
720
Pentagram|
720
Pentagram|
120
Great dodecahedron|
660H4
Self-dual
Great grand 120-cell
120
Great dodecahedron|
720
Pentagon|
1200
Triangle|
120
Great stellated dodecahedron|
76−480H4
Great icosahedral 120-cell
Great icosahedral 120-cell

120
Great icosahedron|
1200
Triangle|
720
Pentagon|
120
Small stellated dodecahedron|
76480H4
Great grand 120-cell
Grand 600-cell
600
Tetrahedron|
1200
Triangle|
720
Pentagram|
120
Great icosahedron|
1910H4
Great grand stellated 120-cell
Great grand stellated 120-cell
120
Great stellated dodecahedron|
720
Pentagram|
1200
Triangle|
600
Tetrahedron|
1910H4
Grand 600-cell

There are 4 failed potential regular star 4-polytopes permutations:,,,. Their cells and vertex figures exist, but they do not cover a hypersphere with a finite number of repetitions.

Five and more dimensions

In five dimensions, a regular polytope can be named as
where is the 4-face type, is the cell type, is the face type, and is the face figure, is the edge figure, and is the vertex figure.
A regular 5-polytope exists only if and are regular 4-polytopes.
The space it fits in is based on the expression:
Enumeration of these constraints produce 3 convex polytopes, zero nonconvex polytopes, 3 4-space tessellations, and 5 hyperbolic 4-space tessellations. There are no non-convex regular polytopes in five dimensions or higher.

Convex

In dimensions 5 and higher, there are only three kinds of convex regular polytopes.
NameSchläfli
Symbol
Coxeterk-facesFacet
type
Vertex
figure
Dual
n-simplex...binomial coefficient|Self-dual
n-cube...n-orthoplex
n-orthoplex...n-cube

There are also improper cases where some numbers in the Schläfli symbol are 2. For example, is an improper regular spherical polytope whenever is a regular spherical polytope, and is an improper regular spherical polytope whenever is a regular spherical polytope. Such polytopes may also be used as facets, yielding forms such as.

5 dimensions


5-simplex

5-cube

5-orthoplex

6 dimensions


6-simplex

6-cube

6-orthoplex

7 dimensions


7-simplex

7-cube

7-orthoplex

8 dimensions


8-simplex

8-cube

8-orthoplex

9 dimensions


9-simplex

9-cube

9-orthoplex

10 dimensions


10-simplex

10-cube

10-orthoplex

...

Non-convex

There are no non-convex regular polytopes in five dimensions or higher.

Regular projective polytopes

A projective regular -polytope exists when an original regular n-spherical tessellation,, is centrally symmetric. Such a polytope is named hemi-, and contain half as many elements. Coxeter gives a symbol /2, while McMullen writes h/2 with h as the coxeter number.
Even-sided regular polygons have hemi-2n-gon projective polygons, /2.
There are 4 regular projective polyhedra related to 4 of 5 Platonic solids.
The hemi-cube and hemi-octahedron generalize as hemi-n-cubes and hemi-n-orthoplexes in any dimensions.

Regular projective polyhedra

Regular projective 4-polytopes

In 4-dimensions 5 of 6 convex regular 4-polytopes generate projective 4-polytopes. The 3 special cases are hemi-24-cell, hemi-600-cell, and hemi-120-cell.
NameCoxeter
symbol
McMullen
Symbol
CellsFacesEdgesVerticesχ
Hemi-tesseract/244121680
Hemi-16-cell/248161240
Hemi-24-cell/26124848120
Hemi-120-cell/215603606003000
Hemi-600-cell/215300600360600

Regular projective 5-polytopes

There are only 2 convex regular projective hemi-polytopes in dimensions 5 or higher.
NameSchläfli4-facesCellsFacesEdgesVerticesχ
hemi-penteract/25204040161
hemi-pentacross/21640402051

Apeirotopes

An apeirotope or infinite polytope is a polytope which has infinitely many facets. An n-apeirotope is an infinite n-polytope: a 2-apeirotope or apeirotope, is an infinite polygon, a 3-apeirotope, or apeirohedron, is an infinite polyhedron, etc.
There are two main geometric classes of apeirotope:
  • Regular honeycombs in n dimensions, which completely fill an n-dimensional space.
  • Regular skew apeirotopes, comprising an n-dimensional manifold in a higher space.

    One dimension (apeirogons)

The straight apeirogon is a regular tessellation of the line, subdividing it into infinitely many equal segments. It has infinitely many vertices and edges. Its Schläfli symbol is, and Coxeter diagram.
......
Apeirogons in the hyperbolic plane, most notably the regular apeirogon,, can have a curvature just like finite polygons of the Euclidean plane, with the vertices circumscribed by horocycles or hypercycles rather than circles.
Regular apeirogons that are scaled to converge at infinity have the symbol and exist on horocycles, while more generally they can exist on hypercycles.

Apeirogon on horocycle

Apeirogon on hypercycle

Above are two regular hyperbolic apeirogons in the Poincaré disk model, the right one shows perpendicular reflection lines of divergent fundamental domains, separated by length λ.

Skew apeirogons

A skew apeirogon in two dimensions forms a zig-zag line in the plane. If the zig-zag is even and symmetrical, then the apeirogon is regular.
Skew apeirogons can be constructed in any number of dimensions. In three dimensions, a regular skew apeirogon traces out a helical spiral and may be either left- or right-handed.
2-dimensions3-dimensions

Zig-zag apeirogon

Helix apeirogon

Two dimensions (apeirohedra)

Euclidean tilings

There are three regular tessellations of the plane. All three have an Euler characteristic of 0.
There are two improper regular tilings:, an apeirogonal dihedron, made from two apeirogons, each filling half the plane; and secondly, its dual,, an apeirogonal hosohedron, seen as an infinite set of parallel lines.

Order-2 apeirogonal tiling|,

Apeirogonal hosohedron|,

Euclidean star-tilings

There are no regular plane tilings of star polygons. There are many enumerations that fit in the plane, like,,,, etc., but none repeat periodically.

Hyperbolic tilings

Tessellations of hyperbolic 2-space are hyperbolic tilings. There are infinitely many regular tilings in H2. As stated above, every positive integer pair such that 1/p + 1/q < 1/2 gives a hyperbolic tiling. In fact, for the general Schwarz triangle the same holds true for 1/p + 1/q + 1/r < 1.
There are a number of different ways to display the hyperbolic plane, including the Poincaré disc model which maps the plane into a circle, as shown below. It should be recognized that all of the polygon faces in the tilings below are equal-sized and only appear to get smaller near the edges due to the projection applied, very similar to the effect of a camera fisheye lens.
There are infinitely many flat regular 3-apeirotopes as regular tilings of the hyperbolic plane, of the form, with p+q
  • ,, ...
  • ,, ...
  • ,, ...
  • ,, ...
  • ,, ...
  • ,, ...
  • ,, ...
  • ...
  • ,, ...
A sampling:

Hyperbolic star-tilings

There are 2 infinite forms of hyperbolic tilings whose faces or vertex figures are star polygons: and their duals with m = 7, 9, 11,.... The tilings are stellations of the tilings while the dual tilings are facetings of the tilings and greatenings of the tilings.
The patterns and continue for odd m < 7 as polyhedra: when m = 5, we obtain the small stellated dodecahedron and great dodecahedron, and when m = 3, the case degenerates to a tetrahedron. The other two Kepler–Poinsot polyhedra do not have regular hyperbolic tiling analogues. If m is even, depending on how we choose to define, we can either obtain degenerate double covers of other tilings or compound tilings.
NameSchläfliCoxeter diagramImageFace type
Vertex figure
DensitySymmetryDual
Order-7 heptagrammic tiling

3*732
Heptagrammic-order heptagonal tiling
Heptagrammic-order heptagonal tiling

3*732
Order-7 heptagrammic tiling
Order-9 enneagrammic tiling

3*932
Enneagrammic-order enneagonal tiling
Enneagrammic-order enneagonal tiling

3*932
Order-9 enneagrammic tiling
Order-11 hendecagrammic tiling

3*11.3.2
Hendecagrammic-order hendecagonal tiling
Hendecagrammic-order hendecagonal tiling

3*11.3.2
Order-11 hendecagrammic tiling
Order-p p-grammic tiling 3*p32
p-grammic-order p-gonal tiling
p-grammic-order p-gonal tiling 3*p32
Order-p p-grammic tiling

Skew apeirohedra in Euclidean 3-space

There are three regular skew apeirohedra in Euclidean 3-space, with regular skew polygon vertex figures. They share the same vertex arrangement and edge arrangement of 3 convex uniform honeycombs.
  • 6 squares around each vertex:
  • 4 hexagons around each vertex:
  • 6 hexagons around each vertex:
,. A π petrie dual operator replaces faces with petrie polygons; δ is a dual operator reverses vertices and faces; φk is a kth facetting operator; η is a halving operator, and σ skewing halving operator.
There are thirty regular apeirohedra in Euclidean 3-space. These include those [|listed above], as well as 8 other "pure" apeirohedra, all related to the cubic honeycomb,, with others having skew polygon faces: 4, 4, 6, a, b, .*3, 6,4, 4,4, and 6,3.

Skew apeirohedra in hyperbolic 3-space

There are 31 regular skew apeirohedra in hyperbolic 3-space:
  • 14 are compact:,,,,,,,,,,,,, and.
  • 17 are paracompact:,,,,,,,,,,,,,,,, and.

    Three dimensions (4-apeirotopes)

Tessellations of Euclidean 3-space

There is only one non-degenerate regular tessellation of 3-space, :
NameSchläfli
Coxeter
Cell
type
Face
type
Edge
figure
Vertex
figure
χDual
Cubic honeycomb0Self-dual

Improper tessellations of Euclidean 3-space

There are six improper regular tessellations, pairs based on the three regular Euclidean tilings. Their cells and vertex figures are all regular hosohedra, dihedra,, and Euclidean tilings. These improper regular tilings are constructionally related to prismatic uniform honeycombs by truncation operations. They are higher-dimensional analogues of the order-2 apeirogonal tiling and apeirogonal hosohedron.
Schläfli
Coxeter
diagram
Cell
type
Face
type
Edge
figure
Vertex
figure
order-4 square hosohedral honeycomb|
Order-6 triangular hosohedral honeycomb|
hexagonal hosohedral honeycomb|
Order-2 square tiling honeycomb|
Order-2 triangular tiling honeycomb|
Order-2 hexagonal tiling honeycomb|

Tessellations of hyperbolic 3-space

There are ten flat regular honeycombs of hyperbolic 3-space:
  • 4 are compact:,,, and
  • while 6 are paracompact:,,,,,,,,,, and.

Tessellations of hyperbolic 3-space can be called hyperbolic honeycombs. There are 15 hyperbolic honeycombs in H3, 4 compact and 11 paracompact.
NameSchläfli
Symbol
Coxeter
Cell
type
Face
type
Edge
figure
Vertex
figure
χDual
Icosahedral honeycombicosahedron|dodecahedron|0Self-dual
Order-5 cubic honeycombcube|icosahedron|0
Order-4 dodecahedral honeycombDodecahedron|octahedron|0
Order-5 dodecahedral honeycombDodecahedron|icosahedron|0Self-dual

There are also 11 paracompact H3 honeycombs :,,,,,,,,,, and.
NameSchläfli
Symbol
Coxeter
Cell
type
Face
type
Edge
figure
Vertex
figure
χDual
Order-6 tetrahedral honeycombtetrahedron|triangular tiling|0
Hexagonal tiling honeycombhexagonal tiling|tetrahedron|0
Order-4 octahedral honeycomboctahedron|square tiling|0
Square tiling honeycombsquare tiling|cube|0
Triangular tiling honeycombtriangular tiling|hexagonal tiling|0Self-dual
Order-6 cubic honeycombCube|octahedron|0
Order-4 hexagonal tiling honeycombhexagonal tiling|Octahedron|0
Order-4 square tiling honeycombsquare tiling|square tiling|0
Order-6 dodecahedral honeycombdodecahedron|icosahedron|0
Order-5 hexagonal tiling honeycombhexagonal tiling|icosahedron|0
Order-6 hexagonal tiling honeycombhexagonal tiling|triangular tiling|0Self-dual

Noncompact solutions exist as Lorentzian Coxeter groups, and can be visualized with open domains in hyperbolic space. All honeycombs with hyperbolic cells or vertex figures and do not have 2 in their Schläfli symbol are noncompact.
There are no regular hyperbolic star-honeycombs in H3: all forms with a regular star polyhedron as cell, vertex figure or both end up being spherical.

Four dimensions (5-apeirotopes)

Tessellations of Euclidean 4-space

There are three kinds of infinite regular tessellations that can tessellate Euclidean four-dimensional space:
NameSchläfli
Symbol
Facet
type
Cell
type
Face
type
Face
figure
Edge
figure
Vertex
figure
Dual
Tesseractic honeycombSelf-dual
16-cell honeycomb
24-cell honeycomb


Projected portion of

Projected portion of

Projected portion of

There are also the two improper cases and.
There are three flat regular honeycombs of Euclidean 4-space:
  • ,, and.
There are seven flat regular convex honeycombs of hyperbolic 4-space:
  • 5 are compact:,,,,
  • 2 are paracompact:, and.
There are four flat regular star honeycombs of hyperbolic 4-space:
  • ,,, and.

    Tessellations of hyperbolic 4-space

There are seven convex regular honeycombs and four star-honeycombs in H4 space. Five convex ones are compact, and two are paracompact.
Five compact regular honeycombs in H4:
NameSchläfli
Symbol
Facet
type
Cell
type
Face
type
Face
figure
Edge
figure
Vertex
figure
Dual
Order-5 5-cell honeycomb5-cell|tetrahedron|icosahedron|600-cell|
120-cell honeycomb120-cell|dodecahedron|tetrahedron|5-cell|
Order-5 tesseractic honeycombtesseract|cube|icosahedron|600-cell|
Order-4 120-cell honeycomb120-cell|dodecahedron|octahedron|16-cell|
Order-5 120-cell honeycomb120-cell|dodecahedron|icosahedron|600-cell|Self-dual

The two paracompact regular H4 honeycombs are:,.
NameSchläfli
Symbol
Facet
type
Cell
type
Face
type
Face
figure
Edge
figure
Vertex
figure
Dual
Order-4 24-cell honeycomb24-cell|octahedron|octahedron|cubic honeycomb|
Cubic honeycomb honeycombcubic honeycomb|cube|cube|24-cell|

Noncompact solutions exist as Lorentzian Coxeter groups, and can be visualized with open domains in hyperbolic space. All honeycombs which are not shown in the set of tables below and do not have 2 in their Schläfli symbol are noncompact.

Star tessellations of hyperbolic 4-space

There are four regular star-honeycombs in H4 space:
NameSchläfli
Symbol
Facet
type
Cell
type
Face
type
Face
figure
Edge
figure
Vertex
figure
DualDensity
Small stellated 120-cell honeycombSmall stellated 120-cell|120-cell|5
Pentagrammic-order 600-cell honeycomb600-cell|tetrahedron|5
Order-5 icosahedral 120-cell honeycombicosahedron|10
Great 120-cell honeycombdodecahedron|10

Five dimensions (6-apeirotopes)

There is only one flat regular honeycomb of Euclidean 5-space:
There are five flat regular regular honeycombs of hyperbolic 5-space, all paracompact:
  • ,,,, and

    Tessellations of Euclidean 5-space

The hypercubic honeycomb is the only family of regular honeycombs that can tessellate each dimension, five or higher, formed by hypercube facets, four around every ridge.
NameSchläfli
Facet
type
Vertex
figure
Dual
Square tilingSelf-dual
Cubic honeycombSelf-dual
Tesseractic honeycombSelf-dual
5-cube honeycombSelf-dual
6-cube honeycombSelf-dual
7-cube honeycombSelf-dual
8-cube honeycombSelf-dual
n-hypercubic honeycombSelf-dual

In E5, there are also the improper cases,,,,, and. In En, and are always improper Euclidean tessellations.

Tessellations of hyperbolic 5-space

There are 5 regular honeycombs in H5, all paracompact, which include infinite facets or vertex figures:,,,, and.
There are no compact regular tessellations of hyperbolic space of dimension 5 or higher and no paracompact regular tessellations in hyperbolic space of dimension 6 or higher.
NameSchläfli
Symbol
Facet
type
4-face
type
Cell
type
Face
type
Cell
figure
Face
figure
Edge
figure
Vertex
figure
Dual
5-orthoplex honeycomb5-orthoplex|5-cell|tetrahedron|cube|24-cell|16-cell honeycomb|
24-cell honeycomb honeycomb24-cell honeycomb|24-cell|octahedron|tetrahedron|5-cell|5-cube|
16-cell honeycomb honeycomb16-cell honeycomb|16-cell|tetrahedron|tetrahedron|tesseract|24-cell honeycomb|self-dual
Order-4 24-cell honeycomb honeycomb16-cell honeycomb|24-cell|octahedron|octahedron|16-cell|Tesseractic honeycomb|
Tesseractic honeycomb honeycombTesseractic honeycomb|Tesseract|Cube|cube|24-cell|16-cell honeycomb|

Since there are no regular star n-polytopes for n ≥ 5, that could be potential cells or vertex figures, there are no more hyperbolic star honeycombs in Hn for n ≥ 5.

6 dimensions and higher (7-apeirotopes+)

Tessellations of hyperbolic 6-space and higher

There are no regular compact or paracompact tessellations of hyperbolic space of dimension 6 or higher. However, any Schläfli symbol of the form not covered above will form a noncompact tessellation of hyperbolic n-space.

Compound polytopes

Two dimensional compounds

For any natural number n, there are n-pointed star regular polygonal stars with Schläfli symbols for all m such that m < n/2 and m and n are coprime. When m and n are not coprime, the star polygon obtained will be a regular polygon with n/m sides. A new figure is obtained by rotating these regular n/m-gons one vertex to the left on the original polygon until the number of vertices rotated equals n/m minus one, and combining these figures. An extreme case of this is where n/m is 2, producing a figure consisting of n/2 straight line segments; this is called a degenerate star polygon.
In other cases where n and m have a common factor, a star polygon for a lower n is obtained, and rotated versions can be combined. These figures are called star figures, improper star polygons or compound polygons. The same notation is often used for them, although authorities such as Grünbaum regard the form k as being more correct, where usually k = m.
A further complication comes when we compound two or more star polygons, as for example two pentagrams, differing by a rotation of 36°, inscribed in a decagon. This is correctly written in the form k, as 2, rather than the commonly used.
Coxeter's extended notation for compounds is of the form c'e, indicating that d distinct 's together cover the vertices of c times and the facets of e times. If no regular exists, the first part of the notation is removed, leaving e; the opposite holds if no regular exists. The dual of c'e is ec. If c or e are 1, they may be omitted. For compound polygons, this notation reduces to : for example, the hexagram may be written thus as .

2

3

4

5

6

7

8

9

10

11

12

13

14

15
-

2

3

4

5

6

7

8

9

10

2

3

4

5

6

7

2

3

4

5

6

2

3

4

5

6

2

3

4

5
-

2

3

4

2

3

4

2

3

4

2

3

2

3
--

2

3

2

3

2

3

2

3

2

3
-----

2

2

2

2

2

2

2

2

2

2

2

2

2
--

2

2

2

2

2

2

2
--------

Regular skew polygons also create compounds, seen in the edges of prismatic compound of antiprisms, for instance:

Three dimensional compounds

A regular polyhedron compound can be defined as a compound which, like a regular polyhedron, is vertex-transitive, edge-transitive, and face-transitive. With this definition there are 5 regular compounds.
Coxeter's notation for regular compounds is given in the table above, incorporating Schläfli symbols. The material inside the square brackets, , denotes the components of the compound: d separate 's. The material before the square brackets denotes the vertex arrangement of the compound: c is a compound of d 's sharing the vertices of an counted c times. The material after the square brackets denotes the facet arrangement of the compound: e is a compound of d 's sharing the faces of counted e times. These may be combined: thus ce is a compound of d 's sharing the vertices of counted c times and the faces of counted e times. This notation can be generalised to compounds in any number of dimensions.

Euclidean and hyperbolic plane compounds

There are eighteen two-parameter families of regular compound tessellations of the Euclidean plane. In the hyperbolic plane, five one-parameter families and seventeen isolated cases are known, but the completeness of this listing has not yet been proven.
The Euclidean and hyperbolic compound families 2 are analogous to the spherical stella octangula, 2.

Four dimensional compounds

lists 32 regular compounds of regular 4-polytopes in his book Regular Polytopes:. McMullen adds six in his paper New Regular Compounds of 4-Polytopes. In the following tables, the superscript indicates that the labeled compounds are distinct from the other compounds with the same symbols.
CompoundConstituentSymmetryVertex arrangementCell arrangement
120 5-cell, order 14400
120 5-cellorder 1200
720 5-cell, order 1440066
5 24-cell, order 14400

Compound 1Compound 2SymmetryVertex arrangement Cell arrangement Vertex arrangement Cell arrangement
3 16-cell|3 tesseract|, order 115222
15 16-cell|15 tesseract|, order 1440022
75 16-cell|75 tesseract|, order 14400510105
75 16-cell|75 tesseract|, order 1440022
75 16-cell|75 tesseract|order 60022
300 16-cell|300 tesseract|+, order 72004884
600 16-cell|600 tesseract|, order 14400816168
25 24-cell|25 24-cell|, order 1440055

There are two different compounds of 75 tesseracts: one shares the vertices of a 120-cell, while the other shares the vertices of a 600-cell. It immediately follows therefore that the corresponding dual compounds of 75 16-cells are also different.
CompoundSymmetryVertex arrangementCell arrangement
5 Great 120-cell|+, order 7200
10 Great 120-cell|, order 1440022
5 Grand stellated 120-cell|+, order 7200
10 Grand stellated 120-cell|, order 1440022

Compound 1Compound 2SymmetryVertex arrangement Cell arrangement Vertex arrangement Cell arrangement
5 Icosahedral 120-cell|5 Small stellated 120-cell|+, order 7200
10 Icosahedral 120-cell|10 Small stellated 120-cell|, order 144002222
5 Great grand 120-cell|5 Great icosahedral 120-cell|+, order 7200
10 Great grand 120-cell|10 Great icosahedral 120-cell|, order 144002222
5 Great stellated 120-cell|5 Grand 120-cell|+, order 7200
10 Great stellated 120-cell|10 Grand 120-cell|, order 144002222

There are also fourteen partially regular compounds, that are either vertex-transitive or cell-transitive but not both. The seven vertex-transitive partially regular compounds are the duals of the seven cell-transitive partially regular compounds.
Compound 1
Vertex-transitive
Compound 2
Cell-transitive
Symmetry
2 16-cells2 tesseracts, order 384
25 24-cell25 24-cellorder 600
100 24-cell100 24-cell+, order 7200
200 24-cell200 24-cell, order 14400
5 600-cell5 120-cell+, order 7200
10 600-cell10 120-cell, order 14400

Although the 5-cell and 24-cell are both self-dual, their dual compounds are not considered to be regular, unlike the compound of two tetrahedra and the various dual polygon compounds, because they are neither vertex-regular nor cell-regular: they are not facetings or stellations of any regular 4-polytope.

Euclidean 3-space compounds

The only regular Euclidean compound honeycombs are an infinite family of compounds of cubic honeycombs, all sharing vertices and faces with another cubic honeycomb. This compound can have any number of cubic honeycombs. The Coxeter notation is .

Five dimensions and higher compounds

There are no regular compounds in five or six dimensions. There are three known seven-dimensional compounds, and six known eight-dimensional ones. There is also one compound of n-simplices in n-dimensional space provided that n is one less than a power of two, and also two compounds in n-dimensional space if n is a power of two.
The Coxeter notation for these compounds are :
  • Simplexes: γn−1βn−1
  • Orthoplexes: γn
  • Hypercubes: βn

    Euclidean honeycomb compounds

A known family of regular Euclidean compound honeycombs in five or more dimensions is an infinite family of compounds of hypercubic honeycombs, all sharing vertices and faces with another hypercubic honeycomb. This compound can have any number of hypercubic honeycombs. The Coxeter notation is δnδn where δn = when n = 2 and when n ≥ 3.

Abstract polytopes

The abstract polytopes arose out of an attempt to study polytopes apart from the geometrical space they are embedded in. They include the tessellations of spherical, Euclidean and hyperbolic space, tessellations of other manifolds, and many other objects that do not have a well-defined topology, but instead may be characterised by their "local" topology. There are infinitely many in every dimension. See for a sample. Some notable examples of abstract regular polytopes that do not appear elsewhere in this list are the 11-cell,, and the 57-cell,, which have regular projective polyhedra as cells and vertex figures.
The elements of an abstract polyhedron are its body, its faces, edges, vertices and the null polytope or empty set. These abstract elements can be mapped into ordinary space or realised as geometrical figures. Some abstract polyhedra have well-formed or faithful realisations, others do not. A flag is a connected set of elements of each dimension - for a polyhedron that is the body, a face, an edge of the face, a vertex of the edge, and the null polytope. An abstract polytope is said to be regular if its combinatorial symmetries are transitive on its flags - that is to say, that any flag can be mapped onto any other under a symmetry of the polyhedron. Abstract regular polytopes remain an active area of research.
Five such regular abstract polyhedra, which can not be realised faithfully, were identified by H. S. M. Coxeter in his book Regular Polytopes and again by J. M. Wills in his paper "The combinatorially regular polyhedra of index 2". They are all topologically equivalent to toroids. Their construction, by arranging n faces around each vertex, can be repeated indefinitely as tilings of the hyperbolic plane. In the diagrams below, the hyperbolic tiling images have colors corresponding to those of the polyhedra images.
These occur as dual pairs as follows:
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