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decahedron

American  
[dek-uh-hee-druhn] / ˌdɛk əˈhi drən /

noun

Geometry.

plural

decahedrons, decahedra
  1. a solid figure having ten faces.


decahedron British  
/ ˌdɛkəˈhiːdrən /

noun

  1. a solid figure having ten plane faces See also polyhedron

"Collins English Dictionary — Complete & Unabridged" 2012 Digital Edition © William Collins Sons & Co. Ltd. 1979, 1986 © HarperCollins Publishers 1998, 2000, 2003, 2005, 2006, 2007, 2009, 2012

decahedron Scientific  
/ dĕk′ə-hēdrən /

plural

decahedrons
  1. A polyhedron having ten faces.


Other Word Forms

  • decahedral adjective

Etymology

Origin of decahedron

From New Latin, dating back to 1820–30; deca-, -hedron

Explanation

In geometry, a solid, three-dimensional shape with ten sides is called a decahedron. In real life, you're most likely to come across a decahedron in the form of a glass or crystal prism. The next time you see one hanging in a window, reflecting rainbows on the wall, count the number of faces, or smooth sides — if there are ten, it's a decahedron. The word comes from Greek roots deka, ten, and hedra, "base" or "face of a geometric solid."

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