- (mathematics) a group of isometries leaving a fixed point
- (biology) any organism that shows polymorphism
- (chemistry),(geology) any substance or mineral that forms different types of crystal
- The ability to assume different forms or shapes.
- (context, crystallography) The ability of a solid material to exist in more than one form or crystal structure; pleomorphism.
- (context, biology) The coexistence, in the same locality, of two or more distinct forms independent of sex, not connected by intermediate gradations, but produced from common parents.
- (context, computer science) The feature of object-oriented programming that allows a method to have several definitions, depending on the types of the arguments it is called with.
- (mathematics) A polyhedron with parallel ends of the same size and shape, the other faces being parallelogram-shaped sides.
- A transparent block in the shape of a prism (typically with triangular ends), used to split or reflect light.
- A crystal in which the faces are parallel to the vertical axis.
- An ancient massive construction with a square or rectangular base and four triangular sides meeting in an apex, such as those built as tombs in Egypt or as bases for temples in Mesoamerica.
- A construction in the shape of a pyramid, usually with a square or rectangular base.
- (geometry) A solid with triangular lateral faces and a polygonal (often square or rectangular) base.
- A pyramid scheme.
noun (plural pyritohedra)
- (mathematics) an irregular dodecahedron, consisting of identical but irregular pentagons
- the shape of a crystal of pyrite