from The American Heritage® Dictionary of the English Language, 4th Edition
- n. A black or dark brown shale containing hydrocarbons that yield petroleum by distillation.
from Wiktionary, Creative Commons Attribution/Share-Alike License
- n. a dark-brown or black shale, from which petroleum-like hydrocarbons can be produced by distillation
from WordNet 3.0 Copyright 2006 by Princeton University. All rights reserved.
- n. shale from which oil can be obtained by heating
Sorry, no etymologies found.