A light-colored igneous rock consisting essentially of alkali feldspar. (noun)
American Heritage(R) Dictionary of the English Language, Fifth Edition. Copyright (c) 2011 by Houghton Mifflin Harcourt Publishing Company. Published by Houghton Mifflin Harcourt Publishing Company. All rights reserved.
Use "trachyte" in a sentence
"The +Puy-de-Dome+ is 4806 ft. above the level of the sea, has no crater, and is covered with a long tufted grass, with here and there a rough spongy rock cropping out, of volcanic origin, and called trachyte, of which the variety found here, and almost here alone, has been named domite."
"Jackson Slater lowered himself over the crumbling rim of the volcanic plug, then dropped into the cooler, shadowy dimness of a rust-colored soda trachyte rock tube."
"About 55 statues are made of other stone – red scoria, basalt, or trachyte – and are smaller than the average size of 5 m."