from The American Heritage® Dictionary of the English Language, 4th Edition
- n. A light gray volcanic rock containing a mixture of plagioclase and other crystalline minerals in glassy silica, similar in appearance to rhyolite.
from Wiktionary, Creative Commons Attribution/Share-Alike License
- n. An igneous, volcanic rock with a high iron content.
from The Century Dictionary and Cyclopedia
- n. A name first used by Fr. Von Hauer and Stache, in 1863, in describing the geology of Transylvania, to include the varieties of greenstone-trachyte which contain quartz.
from WordNet 3.0 Copyright 2006 by Princeton University. All rights reserved.
- n. a grey volcanic rock containing plagioclase and quartz and other crystalline minerals
After Dacia .(American Heritage® Dictionary of the English Language, Fourth Edition)
From German Dazit, from Latin Dācia ("greater Romania"). First used in 1863 by Austrian geologists Franz von Hauer and Guido Stache, in a description of the geology of Transylvania. (Wiktionary)