- 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 trachyte
Walls of grey slate and trachyte, and the yellow stuff is good and plenty.The Trail of a Sourdough
May Kellogg Sullivan
The last is in a sienitic rock on the limits of the trachyte.
The last of the trachyte peaks are at the head of Mosquito pass.
The mines here are found both in the granite and also in the trachyte.
Some of these are composed of trachyte, others of compact blue basalt with olivine.Principles of Geology
- 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
- 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.