nitrogen fixation

noun

: 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

But if they are grown in soil that is too acidic, nitrogen fixation is reduced and pea plants won’t grow well.1 To keep pea crops healthy, grow these plants in rich, well-draining soils with a pH between 6.0 and 7.5. —Lauren Landers, Better Homes & Gardens, 20 Feb. 2025

At present, nitrogen fixation—the chemical process required to produce ammonia from nitrogen gas—is hugely energy intensive, accounting for as much as two percent of the world’s annual energy budget. —Charina Chou, Foreign Affairs, 7 Jan. 2025

Clearly, this is a recurring theme in the world of nitrogen fixation. —Quanta Magazine, 17 July 2024

Legume seeds can be inoculated with rhizobia bacteria before planting to enhance nitrogen fixation even further. —Lauren Landers, Better Homes & Gardens, 1 Aug. 2024

The relationship appears to represent a significant chunk of nitrogen fixation on Earth. —Quanta Magazine, 17 July 2024

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

Word History

First Known Use

1893, in the meaning defined above

Rhymes for nitrogen fixation

• acclimatisation
• acclimatization
• acidification
• actualization
• annualization
• autocorrelation
• autoregulation
• beatification
• beneficiation
• biodegradation
• biotransformation
• bureaucratization

Kids Definition

nitrogen fixation

noun

: 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

noun

1

: the industrial conversion of free nitrogen into combined forms useful especially as starting materials for fertilizers or explosives

2

: 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