methane

noun

meth·​ane ˈme-ˌthān 

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

Mud volcanoes ooze liquified brown sediment and emit shimmering curtains of methane bubbles. —Jeffrey Marlow, New Yorker, 5 Apr. 2026

After three transits, astronomers determined TOI-5205 b possesses an atmosphere with compounds like methane and hydrogen sulphide. —Andrew Paul, Popular Science, 2 Apr. 2026

That region is critical for detecting gases like carbon dioxide and methane. —Aamir Khollam, Interesting Engineering, 2 Apr. 2026

The carbon isotopes are found on 3I/ATLAS in compounds such as carbon monoxide and carbon dioxide, and even organic molecules such as methanol, formaldehyde and methane. —Keith Cooper, Space.com, 30 Mar. 2026

Word History

Etymology

International Scientific Vocabulary

First Known Use

1867, in the meaning defined above

Rhymes for methane

• abstain
• airplane
• alkane
• arcane
• arraign
• attain
• backplane
• betaine
• biplane
• blockchain
• butane
• campaign

Kids Definition

methane

noun

meth·​ane ˈmeth-ˌān 

: 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