trigonal


Also found in: Thesaurus, Medical, Encyclopedia, Wikipedia.
Related to trigonal: monoclinic, rhombohedral

tri·go·nal

 (trī-gō′nəl)
adj. Mineralogy
Rhombohedral.

[Earlier, relating to a trigon or triplicity, relating to three angles : Latin trigōnum, triangle; see trigon + -al.]
American Heritage® Dictionary of the English Language, Fifth Edition. Copyright © 2016 by Houghton Mifflin Harcourt Publishing Company. Published by Houghton Mifflin Harcourt Publishing Company. All rights reserved.

trigonal

(ˈtrɪɡənəl)
adj
1. (Mathematics) another word for triangular1
2. (Chemistry) 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 and Unabridged, 12th Edition 2014 © HarperCollins Publishers 1991, 1994, 1998, 2000, 2003, 2006, 2007, 2009, 2011, 2014

trig•o•nal

(ˈtrɪg ə nl)

adj.
1. of, pertaining to, or shaped like a triangle; having three angles; triangular.
2. (of a crystal) having threefold symmetry.
[1560–70]
trig′o•nal•ly, adv.
Random House Kernerman Webster's College Dictionary, © 2010 K Dictionaries Ltd. Copyright 2005, 1997, 1991 by Random House, Inc. All rights reserved.

tri·go·nal

(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 more at crystal.
The American Heritage® Student Science Dictionary, Second Edition. Copyright © 2014 by Houghton Mifflin Harcourt Publishing Company. Published by Houghton Mifflin Harcourt Publishing Company. All rights reserved.
ThesaurusAntonymsRelated WordsSynonymsLegend:
Adj.1.trigonal - having threefold symmetry
crystallography - the branch of science that studies the formation and structure of crystals
symmetric, symmetrical - having similarity in size, shape, and relative position of corresponding parts
Based on WordNet 3.0, Farlex clipart collection. © 2003-2012 Princeton University, Farlex Inc.
References in periodicals archive ?
The Molymod Shapes of Molecules Model is an educational aid designed for students with learning disabilities to teach them how to create eight models that feature examples of coordination numbers 1 to 6, including linear hydrogen chloride, linear beryllium chloride, bent water, trigonal planar, pyramidal ammonia, tetrahedral methane, trigonal bipyramidal and octahedral sulfur hexafluoride.
When the simulation trajectories were played back, the CO2 molecules were seen bending from their linear O=C=O shape to form trigonal CO3 units bonded with the quartz.
1 show that all the peaks coincide with those of calcite containing magnesium (Ca, Mg)CO3 (JCPDS 43-0697), which is indexed in the trigonal system with the R-3c space group (No.
Patients' distribution according to fistula diameter, localization, and etiology Patient Age Diameter (cm) Localization Etiology 1 24 1.5 Supratrigonal Vaginal Birth 2 23 1.7 Trigonal Vaginal Birth 3 31 2 Supratrigonal Vaginal Birth 4 34 3 Supratrigonal Vaginal Birth 5 32 2.4 Supratrigonal Vaginal Birth 6 27 2.2 Trigonal Vaginal Birth 7 41 2.8 Supratrigonal Vaginal Hysterectomy 8 26 2 Supratrigonal Vaginal Birth 9 26 2 Supratrigonal Vaginal Birth 10 30 2 Trigonal Vaginal Birth 11 28 2.5 Supratrigonal Vaginal Birth 12 34 2.6 Trigonal Vaginal Birth 13 23 1.8 Supratrigonal Vaginal Birth 14 20 1.5 Supratrigonal Vaginal Birth Table 2.
Monsour is cast in "The Trigonal" set for international release.
Under this, the following are listed for exhibitions: Neomanila by Mikhail Red (PelikulaRED), Dormitoryo by Emerson Reyes (TBA Studios), Nervous Translation by Shireen Seno (Cinema One Originals, Cinematografica), Respeto by Treb Monteras (ArkeoFilms), and The Trigonal: Fight for Justice by Vincent Soberano (Cinefenio Productions).
Contrast enhanced brain magnetic resonance imaging (MRI) was performed after 20 hours, which showed mild diffuse cerebral edema and hydrocephalus with symmetric dilatation of the lateral ventricles (~1.7 cm at trigonal level) bilaterally, and periventricular interstitial edema.
Medial aspects of ureters gently dissected from surrounding tissues till hiatus and trigonal muscles up to advantis layer without damage to ureters in order to make the orifices free; in other words, waldeyer's sheath of bladder dissected completely from medial aspect of intramural ureter carefully so that by this action, approximation of ureter to midline would be tension free.
From the values of bond lengths and coordination numbers, we can conclude that the network structure is constructed through connection of tetrahedral Ge[Se.sub.4] and trigonal Ge[Se.sub.3] structural units.
However, antimony(III) is generally hexacoordinated, and the stereochemistry of antimony(III) complexes is usually based on a distorted trigonal bipyramid with a pair of active lone electrons in one of the trigonal planar sites.
Recently, theoretical predictions and experimental results confirmed that the TaS2 built from the edge-sharing of Ta[S.sub.6] trigonal prisms exhibits superior catalytic performance in comparison with that of Ta[S.sub.6] octahedra [6, 7].