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trihedron

American  
[trahy-hee-druhn] / traɪˈhi drən /

noun

Geometry.

plural

trihedrons, trihedra

  1. the figure determined by three planes meeting in a point.

trihedron British  
/ traɪˈhiːdrən /

noun

  1. a figure determined by the intersection of three planes

"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

Etymology

Origin of trihedron

First recorded in 1820–30; tri- + -hedron

Definitions and idiom definitions from Dictionary.com Unabridged, based on the Random House Unabridged Dictionary, © Random House, Inc. 2023

Idioms from The American Heritage® Idioms Dictionary copyright © 2002, 2001, 1995 by Houghton Mifflin Harcourt Publishing Company. Published by Houghton Mifflin Harcourt Publishing Company.