ammonium

noun
am·​mo·​ni·​um | \ ə-ˈmō-nē-əm How to pronounce ammonium (audio) \

Definition of ammonium

: an ion NH4+ derived from ammonia by combination with a hydrogen ion and known in compounds (such as salts) that resemble in properties the compounds of the alkali metals

Examples of ammonium in a Sentence

Recent Examples on the Web SurfaceWise2′s active ingredient is quaternary ammonium, which is widely used as a disinfectant in hospitals against bacteria, fungi and certain viruses. Ashton Nichols, Dallas News, "Dallas company touts its spray-on coating as a COVID-19 killer for surfaces," 2 June 2020 And in soils that contain nitrate but little to no ammonium, cranberries, blueberries, rhododendrons and azaleas are, for the most part, a non-starter. Paul Cappiello, The Courier-Journal, "Jellied or whole? Thank this lucky soil for whatever Thanksgiving cranberry sauce you eat," 22 Nov. 2019 Fire sparks the reaction between aluminum and ammonium perchlorate that turns solid rocket fuel into the driving force of space travel (NASA’s rocket boosters reach 5,000°F during launch). Vince Guerrieri, Popular Mechanics, "Why Fire Is the Greatest Tool of All Time," 17 Feb. 2020 In the experiments, the phytoplankton greedily sucked up the available organic and inorganic nitrogen coming off the ash in the form of nitrite, nitrate, and ammonium. Jenessa Duncombe, Smithsonian Magazine, "Could Wildfire Ash Feed the Ocean’s Tiniest Life-Forms?," 4 Mar. 2020 Officials said the package appeared to be a bomb and smelled like ammonium. Fox News, "Pro-life event in Minnesota disrupted by bomb threat, officials said," 19 Sep. 2019 The most common retardants in this category use ammonium polyphosphate as the retardant, mixed into a formulation called PC that distributes it. Cathleen O'grady, Ars Technica, "New gel lets us spread flame retardant before wildfires start," 5 Oct. 2019 There have been studies that predict ammonia, ammonium hydrosulfide, and water residing in Jupiter's upper atmosphere. David Grossman, Popular Mechanics, "Hey, What's Up With Jupiter's Great Red Spot?," 12 Aug. 2019 Below, a colorless ammonium hydrosulfide layer could be reacting with cosmic rays or solar UV radiation. David Grossman, Popular Mechanics, "Hey, What's Up With Jupiter's Great Red Spot?," 12 Aug. 2019

These example sentences are selected automatically from various online news sources to reflect current usage of the word 'ammonium.' Views expressed in the examples do not represent the opinion of Merriam-Webster or its editors. Send us feedback.

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First Known Use of ammonium

1808, in the meaning defined above

History and Etymology for ammonium

New Latin, from ammonia

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Time Traveler for ammonium

Time Traveler

The first known use of ammonium was in 1808

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Statistics for ammonium

Last Updated

16 Jun 2020

Cite this Entry

“Ammonium.” Merriam-Webster.com Dictionary, Merriam-Webster, https://www.merriam-webster.com/dictionary/ammonium. Accessed 4 Jul. 2020.

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More Definitions for ammonium

ammonium

noun
am·​mo·​ni·​um | \ ə-ˈmō-nē-əm How to pronounce ammonium (audio) \

Medical Definition of ammonium

: an ion NH4+ derived from ammonia by combination with a hydrogen ion and known in organic compounds (as quaternary ammonium compounds) and in compounds (as salts) that resemble in properties the compounds of the alkali metals

More from Merriam-Webster on ammonium

Britannica English: Translation of ammonium for Arabic Speakers

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