tesseract

From tessara- (“four-”) +‎ Ancient Greek ἀκτίς (aktís, “ray”).

tesseract (plural tesseracts)

1. (mathematics, geometry) The four-dimensional analogue of a cube; a 4D polytope bounded by eight cubes (analogously to the way a cube is bounded by six squares).
   • 1906, Charles Howard Hinton, The Fourth Dimension, S. Sonnenschein & Company, page 239:

     Hence the cube determined by these axes is the face of the tesseract which we now have before us.

   • 1910, Henry Parker Manning, The Fourth Dimension Simply Explained, Munn, Incorporated, page 93:

     […] then it would trace out a higher cube, or tesseract, and each of the six surrounding cubes, carried on in the same motion, would trace tesseracts also, […] .

2. (science fiction) Any of various fictional mechanisms that explain extradimensional, superluminal, or time travel outside the geometry of the physical universe.
   • 1962, Madeleine L'Engle, A Wrinkle in Time, published 2019, unnumbered page:

     "I shall just sit down for a moment and pop on my boots and then I'll be on my way. Speaking of ways, pet, by the way, there is such a thing as a tesseract."

• (analogue of a cube): four-dimensional hypercube, 4-cube, 8-cell, octachoron, tetracube

• hypercube, polytope, polychoron

• tesseractic

• tessera

• Tesseract on Wikipedia.Wikipedia
• Tesseract (disambiguation) on Wikipedia.Wikipedia
• Tesseract on Wolfram MathWorld

• rascettes