Trihedral is a 9 letter English word. It's valid Words with friends word worth 13 points.
You can make 454 anagrams from letters in trihedral (adehilrrt).
First recorded in 1780-90; tri- + -hedral
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.
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