coal gas

from The American Heritage® Dictionary of the English Language, 5th Edition.

• noun A gaseous mixture produced by the destructive distillation of bituminous coal and used as a commercial fuel.
• noun The gaseous mixture released by burning coal.

from The Century Dictionary.

• noun The gas which is given out by burning coal.
• noun A mixture of gases and vapors, chiefly combustible, which is employed to produce the gas-light in common use.

from Wiktionary, Creative Commons Attribution/Share-Alike License.

• noun petrochemistry The poisonous gas, used domestically for cooking etc and formerly for lighting, prepared by heating coal with steam; it is a mixture of hydrogen and carbon monoxide; synthesis gas or town gas.

from WordNet 3.0 Copyright 2006 by Princeton University. All rights reserved.

• noun gaseous mixture produced by distillation of bituminous coal and used for heating and lighting