methane

noun

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
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The Yolo County Central Landfill will build a new system that will convert methane from decomposing waste into renewable natural gas, the county announced Tuesday. Daniel Lempres, Sacbee.com, 30 June 2026 Indeed, reducing methane emissions is an essential goal in reducing the growing threat of climate change. Chicago Tribune, 28 June 2026 Satellite systems are revealing methane levels that dwarf official reporting. Anjali Chaudhry, Forbes.com, 25 June 2026 My previous reporting has shown that a former lobbyist for Hildebrand’s company — who now has a top post at the Environmental Protection Agency — has been rewriting methane regulations with advice from the oil industry. Alex Cuadros, ProPublica, 23 June 2026 See All Example Sentences for methane

Word History

Etymology

International Scientific Vocabulary

First Known Use

1867, in the meaning defined above

Time Traveler
The first known use of methane was in 1867

Cite this Entry

“Methane.” Merriam-Webster.com Dictionary, Merriam-Webster, https://www.merriam-webster.com/dictionary/methane. Accessed 4 Jul. 2026.

Kids Definition

methane

noun
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

methane

noun
meth·​ane
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

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