nitrogen fixation


: the conversion of atmospheric nitrogen into a combined form (such as ammonia) through chemical and especially biological action (such as that of soil rhizobia)

Examples of nitrogen fixation in a Sentence

Recent Examples on the Web There are other approaches to possibly increasing nitrogen fixation on cropland. Matthew Hutson, The New Yorker, 6 Feb. 2024 With governments and private foundations recently providing strong support for research and development in the area of engineering nitrogen fixation, crops that harness the power of natural symbiosis might soon become a key element of a more sustainable food production. Scientific American, 1 Dec. 2021 This knowledge has inspired exciting new approaches to engineering nitrogen fixation into nonlegume plants. Scientific American, 1 Dec. 2021 But symbiosis does not come free, and bacterial nitrogen fixation is not as reliable as fertilizer application. Vaclav Smil, IEEE Spectrum, 3 June 2018 This is known as nitrogen fixation. Matt Simon, WIRED, 30 Aug. 2022 It’s called nitrogen fixation. Paul Tullis,, 16 Feb. 2022 For decades, Cocking believed, as other scientists did, that nitrogen fixation could only occur in the root nodules of legumes. Tracy Staedter, Discover Magazine, 7 Oct. 2019 Joyn’s idea is to synthesize variations on some of the genes that are believed to play a role in nitrogen fixation, including those involved in the cooperation between legumes and the bacteria specific to their root systems. Elie Dolgin, IEEE Spectrum, 31 May 2018

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

Word History

First Known Use

1893, in the meaning defined above

Time Traveler
The first known use of nitrogen fixation was in 1893

Dictionary Entries Near nitrogen fixation

Cite this Entry

“Nitrogen fixation.” Dictionary, Merriam-Webster, Accessed 15 Apr. 2024.

Kids Definition

nitrogen fixation

: the changing of free nitrogen in the air into a combined form (as ammonia) especially by bacteria in the soil and in roots

Medical Definition

nitrogen fixation

: the industrial conversion of free nitrogen into combined forms useful especially as starting materials for fertilizers or explosives
: the metabolic assimilation of atmospheric nitrogen by soil microorganisms and especially rhizobia and its release for plant use by nitrification in the soil on the death of the microorganisms

More from Merriam-Webster on nitrogen fixation

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