from The American Heritage® Dictionary of the English Language, 4th Edition
- n. A banded or foliated metamorphic rock, usually of the same composition as granite.
from Wiktionary, Creative Commons Attribution/Share-Alike License
- n. A common and widely-distributed metamorphic rock having bands or veins, but not schistose.
from the GNU version of the Collaborative International Dictionary of English
- n. A crystalline rock, consisting, like granite, of quartz, feldspar, and mica, but having these materials, especially the mica, arranged in planes, so that it breaks rather easily into coarse slabs or flags. Hornblende sometimes takes the place of the mica, and it is then called hornblendic gneiss or syenitic gneiss. Similar varieties of related rocks are also called gneiss.
from The Century Dictionary and Cyclopedia
- n. A rock which consists essentially of the same mineral elements as granite, namely orthoclase, quartz, and mica, but in which there is a more or less distinctly foliated arrangement of the constituent minerals, and especially of the mica.
from WordNet 3.0 Copyright 2006 by Princeton University. All rights reserved.
- n. a laminated metamorphic rock similar to granite
German Gneis, probably alteration of Middle High German ganeist, spark (from its appearance), from Old High German gneista.(American Heritage® Dictionary of the English Language, Fourth Edition)
From German Gneis, from Middle High German gneist ("spark"), from Old High German gneisto ("spark"). More at gnast. (Wiktionary)