from The American Heritage® Dictionary of the English Language, 4th Edition
- n. Natural glass produced by the cooling of molten lava too quickly to permit crystallization.
from the GNU version of the Collaborative International Dictionary of English
- adj. the vitreous form of lava, produced by sudden cooling; obsidian. See Obsidian.
from WordNet 3.0 Copyright 2006 by Princeton University. All rights reserved.
- n. a kind of natural glass produced when molten lava cools very rapidly
Sorry, no etymologies found.