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flexagon

[flek-suh-gon, -guh n]

noun

a three-dimensional figure having polygonal faces that is constructed from a folded sheet of paper in such a way that different faces are exposed when the figure is flexed along its folds.

Origin of flexagon

flex1 + -agon (as in hexagon, pentagon, etc.)
Dictionary.com Unabridged Based on the Random House Unabridged Dictionary, © Random House, Inc. 2019