noun
- Plural of heptahedron; polyhedra (three-dimensional solid figures) with seven faces.
Usage: mathematics; geometry
Examples
- The student studied various heptahedrons in her advanced geometry class.
- Heptahedrons are less common than cubes or tetrahedrons in basic geometry.
- The mathematician classified different types of heptahedrons by their face shapes.
- In crystallography, certain heptahedrons appear as natural mineral formations.