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Glite Dictionary
📏 An angle 📐 Angle between planes 🔄 Polygon symmetries
dihedral

dihedral

9.9
The movements that turn or flip a regular shape, like a triangle, so it looks the same
  • noun
  • /daɪˈhɛdrəl/
  • Specialized
translation icon : grupo diedral
  • In mathematics, the dihedral group of a square includes rotations and reflections that map the square onto itself.

Examples

  • The symmetries of a regular triangle can be described by its dihedral group, which consists of three rotations and three reflections.

  • I would I would say that permutation is you said Sigma is a permutation about the dihedral group and then you said a permutation of the dihedral group.

  • When studying polygons, the dihedral group helps illustrate how many ways the shape can be manipulated while retaining its original appearance.

Compounds

dihedral angle
  • Specialized
1 8.8

The angle between two flat surfaces that meet along a line

Surface Forms

dihedral singular
dihedrals plural

Morphology

dihedral = di + hedr + al

Although 'di-' suggests 'two', the classical stem 'hedr' and the mathematical meaning of the noun are not transparent to an average B1 learner.

Etymology

Dihedral comes from the Greek parts di- 'two' and -hedral 'face'. A helpful way to remember the mathematical dihedral is to think of two kinds of moves, 'turns' and 'flips', so the name fits the symmetry group of a polygon because it has these two 'faces' of action.