flexagon
/ˈflɛksəɡ(ə)n/Mathematics
noun
Originally: a strip of paper marked with equilateral triangles, alternately upright and inverted and each typically decorated with a pattern or colour, which can be folded into the shape of a regular hexagon in a number of different ways; a hexagon made in this way, which can be manipulated to display different faces in different combinations. In later use also: any regular polygon made in this way.
- A prefix is often used to specify the number of sides of a given flexagon, as in hexaflexagon, tetraflexagon. A further prefix is sometimes used to specify the number of faces the flexagon can display, as in hexahexaflexagon..
Origin
1950s; earliest use found in Mathematical Gazette. Blend of flex and hexagon.