trigonal

[ trig-uh-nl ]
/ ˈtrɪg ə nl /

adjective

of, relating to, or shaped like a triangle; having three angles; triangular.
Crystallography. having threefold symmetry.

Origin of trigonal

First recorded in 1560–70; trigon + -al1
Related formstrig·o·nal·ly, adverbsub·trig·o·nal, adjective
Dictionary.com Unabridged Based on the Random House Unabridged Dictionary, © Random House, Inc. 2019

Examples from the Web for trigonal

British Dictionary definitions for trigonal

trigonal

/ (ˈtrɪɡənəl) /

adjective

another word for triangular (def. 1)
Also: rhombohedral relating or belonging to the crystal system characterized by three equal axes that are equally inclined and not perpendicular to each other
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

Science definitions for trigonal

trigonal

[ trī-gōnəl ]

Relating to a crystal having three axes of equal length intersecting at oblique angles. This crystal system is considered a subset of the hexagonal system. The mineral quartz has trigonal crystals. Also called rhombohedral See illustration at crystal.
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