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tetrahedron

American  
[te-truh-hee-druhn] / ˌtɛ trəˈhi drən /

noun

plural

tetrahedrons, tetrahedra
  1. Geometry. a solid contained by four plane faces; a triangular pyramid.

  2. any of various objects resembling a tetrahedron in the distribution of its faces or apexes.


tetrahedron British  
/ ˌtɛtrəˈhiːdrən /

noun

  1. a solid figure having four plane faces. A regular tetrahedron has faces that are equilateral triangles See also polyhedron

  2. any object shaped like a tetrahedron

"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

tetrahedron Scientific  
/ tĕt′rə-hēdrən /

plural

tetrahedrons
  1. A polyhedron having four faces.


Other Word Forms

  • tetrahedral adjective
  • tetrahedrally adverb

Etymology

Origin of tetrahedron

1560–70; tetra- + -hedron, modeled on Late Greek tetráedron, noun use of neuter of tetráedros four-sided