Dictionary.com
Thesaurus.com
Synonyms

trigonal

American  
[trig-uh-nl] / ˈtrɪg ə nl /

adjective

  1. of, relating to, or shaped like a triangle; having three angles; triangular.

  2. Crystallography. having threefold symmetry.


trigonal British  
/ ˈtrɪɡənəl /

adjective

  1. another word for triangular

  2. 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

trigonal Scientific  
/ trī-gōnəl /
  1. 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.

  2. Also called rhombohedral

  3. See illustration at crystal


Other Word Forms

Etymology

Origin of trigonal

First recorded in 1560–70; trigon + -al 1

Example Sentences

Examples are provided to illustrate real-world usage of words in context. Any opinions expressed do not reflect the views of Dictionary.com.

In typical alkenes, the carbons adopt a trigonal planar geometry, creating a flat structure around the double bond.

From Science Daily • Jan. 23, 2026

They believed the reason trigonal chloride electrolytes can achieve low ionic conductivity is based on the variation of metal ion arrangements within the structure.

From Science Daily • Nov. 2, 2023

In both aldehydes and ketones, the geometry around the carbon atom in the carbonyl group is trigonal planar; the carbon atom exhibits sp2 hybridization.

From Textbooks • Feb. 14, 2019

These properties relate to its structure, which consists of layers of carbon atoms, with each atom surrounded by three other carbon atoms in a trigonal planar arrangement.

From Textbooks • Feb. 14, 2019

Bill short, strong, conic, base trigonal, sides compressed, culmin elevated, upper mandible towards the tip deflexed and notched, under mandible shorter and straight, the base thick, the margins of both inflexed.

From Zoological Illustrations, Volume III or Original Figures and Descriptions of New, Rare, or Interesting Animals by Swainson, William

Vocabulary.com logo
by dictionary.com

Look it up. Learn it forever.

Remember "trigonal" for good with VocabTrainer. Expand your vocabulary effortlessly with personalized learning tools that adapt to your goals.

Take me to Vocabulary.com