meth·​ane ˈme-ˌthān How to pronounce methane (audio)
 British usually  ˈmē-
: a colorless odorless flammable gaseous hydrocarbon CH4 that is a product of biological decomposition of organic matter and of the carbonization of coal, is used as a fuel and as a starting material in chemical synthesis, and is the simplest of the alkanes

Examples of methane in a Sentence

Recent Examples on the Web The world will continue to warm until humans figure out how to curb greenhouse gas emissions, like carbon dioxide and methane. Evan Bush, NBC News, 2 Aug. 2023 Usually obscured by a thick atmosphere, JWST was able to penetrate Titan’s cloud tops to reveal surface features like Kraken Mare, a sea of liquid methane. Dean Regas, The Enquirer, 8 Sep. 2023 Sea ice decline could eventually lead to extinction Greenhouse gases such as carbon dioxide and methane are produced from the burning of fossil fuels such as oil, gas and coal. Doyle Rice, USA TODAY, 1 Sep. 2023 The team says this is a completely new type of feature compared to the smaller ‘companion’ clouds of high-altitude methane ice that astronomers have previously observed. Laura Baisas, Popular Science, 24 Aug. 2023 Water vapor is actually a greenhouse gas, like carbon dioxide or methane, responsible for about half of the planet-warming effect. WIRED, 27 July 2023 Organic waste like vegetable trimmings, egg shells, cardboard and lawn clippings (which should stay on your lawn, by the way, as cheap and useful fertilizer) are the chief contributors to methane gas in our landfills. Jeanette Marantos, Los Angeles Times, 24 Aug. 2023 The Microwave Plasma Chemical Vapor Deposition reactor, which uses microwave power to break down methane and hydrogen gases to grow diamonds in the lab, has now been moved to a basement room of the new building. Greg Garrison | , al, 17 Aug. 2023 The focus on the animals' rear ends also misses their most potent source of methane, Mitloehner said. Nate Trela, USA TODAY, 11 Aug. 2023 See More

These examples are programmatically compiled from various online sources to illustrate current usage of the word 'methane.' Any opinions expressed in the examples do not represent those of Merriam-Webster or its editors. Send us feedback about these examples.

Word History


International Scientific Vocabulary

First Known Use

1867, in the meaning defined above

Time Traveler
The first known use of methane was in 1867

Dictionary Entries Near methane

Cite this Entry

“Methane.” Dictionary, Merriam-Webster, Accessed 3 Oct. 2023.

Kids Definition


meth·​ane ˈmeth-ˌān How to pronounce methane (audio)
: a colorless odorless flammable gas that consists of carbon and hydrogen and is produced by decay of organic matter

Medical Definition


ˈmeth-ˌān, British usually ˈmē-ˌthān
: a colorless, odorless, flammable, gaseous hydrocarbon CH4 that is lighter than air, forms explosive mixtures with air or oxygen, and occurs naturally as a by-product of the decomposition of organic matter by anaerobic bacteria

called also marsh gas

More from Merriam-Webster on methane

Last Updated: - Updated example sentences
Love words? Need even more definitions?

Subscribe to America's largest dictionary and get thousands more definitions and advanced search—ad free!