methane

American  

[meth-eyn, mee-theyn] / ˈmɛθ eɪn, ˈmi θeɪn /

noun

Chemistry.

• methanes
  plural

1. a colorless, odorless, flammable gas, CH 4 , the main constituent of marsh gas and the firedamp of coal mines, obtained commercially from natural gas: the first member of the methane, or alkane, series of hydrocarbons.

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methane British  

/ ˈmiːθeɪn /

noun

1. a colourless odourless flammable gas, the simplest alkane and the main constituent of natural gas: used as a fuel. Formula: CH 4 See also marsh gas firedamp

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methane Scientific  

/ mĕth′ān′ /

1. A colorless, odorless, flammable gas that is the simplest hydrocarbon. It is the major constituent of natural gas and is released during the decomposition of plant or other organic compounds, as in marshes and coal mines. Methane is the first member of the alkane series. Chemical formula: CH ₄ .

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Other Word Forms

Noun Inflected Forms

• methanes
  plural

Etymology

Origin of methane

First recorded in 1865–70; meth- + -ane

Explanation

Methane, a colorless, odorless gas that occurs naturally on Earth, is a component in natural gas. It's also one of the major contributors to climate change. Methane is highly flammable, and it comprises as much as 90 percent of the natural gas that's commonly used for heating, cooking, and generating electricity. Although the release of methane into the atmosphere is a natural process, too much of it contributes to the greenhouse effect, trapping heat in the atmosphere and warming the planet. Methane was discovered by an Italian scientist in 1776, who collected the gas as it rose from a marsh.

Example Sentences

See Examples For:

methane

But the gas that’s released in larger quantities is methane, which forms underwater as plants and algae break down and then bubbles to the surface.

From Los Angeles Times ● Aug. 27, 2026

For the past two years, leftover food has been able to be taken to an anaerobic digester to be converted into methane to generate electricity and produce fertiliser.

From BBC ● Aug. 27, 2026

The Southern Utes’ reservation occupies about 1,100 square miles in the San Juan Basin, atop one of the most productive coal-bed methane fields in the U.S.

From The Wall Street Journal ● Aug. 21, 2026

While less polluting than coal, gas plants are still significant sources of planet-warming emissions, and their operations, particularly upstream, also leak methane, the main component of natural gas and itself a powerful greenhouse gas.

From Barron's ● Aug. 7, 2026

Perhaps it is due to complex brightly colored organic molecules produced when ultraviolet light from the Sun breaks down the methane, ammonia, and water in the Jovian atmosphere and the molecular fragments recombine.

From "Cosmos" by Carl Sagan