trihedral [trahy-hee-druh l] EXAMPLES|WORD ORIGIN adjective Geometry. having, or formed by, three planes meeting in a point: a trihedral angle. noun a trihedron.
Origin of trihedral First recorded in 1780–90;+ Related formssub·tri·he·dral, adjective Dictionary.com Unabridged Based on the Random House Unabridged Dictionary, © Random House, Inc. 2019 Examples from the Web for trihedral Historical Examples of trihedral
The angle between two planes is termed dihedral, between three trihedral, between any number more than three polyhedral.
A triangle and a trihedral angle are therefore reciprocal figures.
British Dictionary definitions for trihedral trihedral adjective having or formed by three plane faces meeting at a point noun a figure formed by the intersection of three lines in different planes Word Origin for trihedral C18: from tri- + Greek hedra base, seat + -al 1 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