trigonal
[trig-uh-nl]
- of, relating to, or shaped like a triangle; having three angles; triangular.
- Crystallography. having threefold symmetry.
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Origin of trigonal
Dictionary.com Unabridged
Based on the Random House Unabridged Dictionary, © Random House, Inc. 2018
Examples from the Web for trigonal
Historical Examples
The leaves are trigonal; they are very short, and they are laid over each other like scales in four rows.
Botany for LadiesJane Loudon
Trigonal trapezohedron (fig. 74), bounded by six trapezoidal faces.
All other forms, in which the faces are neither parallel nor perpendicular to the triad axis, are trigonal pyramids.
Fig. 73 represents a crystal of tourmaline with the trigonal prism , hexagonal prism , and a trigonal pyramid at each end.
Parietes ribbed, mottled purplish-red; orifice broad, trigonal, hardly toothed.
A Monograph on the Sub-class Cirripedia (Volume 2 of 2)Charles Darwin
trigonal
- 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
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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
[trī-gō′nəl]
- 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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The American Heritage® Science Dictionary
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