- a fine-grained volcanic rock consisting essentially of alkali feldspar and one or more subordinate minerals, as hornblende or mica: the extrusive equivalent of syenite.
Origin of trachyte
1815–25; < French < Greek trāchýtēs roughness, equivalent to trāchý(s) rough + -tēs noun suffix
Dictionary.com Unabridged Based on the Random House Unabridged Dictionary, © Random House, Inc. 2018
Examples from the Web for trachytic
The building material was trachytic rock as found upon the mesa.The Prehistoric World
E. A. Allen
This mountain appears to be formed mainly of trachytic matter.Volcanoes: Past and Present
Chimborazo is very likely not a solid mountain: trachytic volcanoes are supposed to be full of cavities.The Andes and the Amazon
Some of the trachytic lavas are said to abound with crystals of albite.
In New Zealand, numerous regions abound in basaltic and trachytic rocks.
- (of the texture of certain igneous rocks) characterized by a parallel arrangement of crystals, which mark the flow of the lava when still molten
- a light-coloured fine-grained volcanic rock of rough texture consisting of feldspars with small amounts of pyroxene or amphibole
C19: from French, from Greek trakhutēs, from trakhus rough
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
- A light-colored, fine-grained igneous rock consisting primarily of alkali feldspar together with some mafic minerals, especially hornblende. Unlike most igneous rocks, trachyte has little or no quartz. Trachyte is the fine-grained equivalent of syenite.
The American Heritage® Science Dictionary Copyright © 2011. Published by Houghton Mifflin Harcourt Publishing Company. All rights reserved.