am·​mo·​ni·​um | \ ə-ˈmō-nē-əm \

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

The process is strongly inhibited in the presence of ammonium, which mainly comes from proteins in waste. David Grossman, Popular Mechanics, "Bacteria Could Transform Human Feces and Wastewater Into Energy," 13 Nov. 2018 In a side room occupied by two goats, the Afghans found a homemade grenade fashioned out of ammonium-nitrate explosives in a blue Party Extreme energy-drink can. Michael M. Phillips, WSJ, "‘I Think I’ve Been Shot’: Nighttime Raid in Afghanistan Reveals New U.S. Strategy," 5 Dec. 2018 The middle of the cylinder is filled with a powdered mixture of ammonium perchlorate and ammonium nitrate, the oxidants. The Economist, "A rocket that devours itself," 31 May 2018 Scientists found higher than normal levels of ammonium and nitrogen, ingredients of the fertilizer. Carrie Blackmore Smith,, "'Human error' caused barge to crack in half and spill fertilizer into the Ohio River," 4 Apr. 2018 In another building at Promontory, the segments are lowered into an underground shaft where they will be loaded with solid rocket fuel, a mixture of aluminum powder fuel and ammonium perchlorate as the oxidizer. Joe Pappalardo, Popular Mechanics, "Solid Rocket City: The Utah Space Center Fighting for Its Life," 4 Apr. 2018 The drink does contain ammonium ferric citrate, which is technically iron, but it is not brewed. Palko Karasz, New York Times, "Irn Bru, a Scottish Favorite, Loses Some Sugar," 5 Jan. 2018 Takata uses the chemical ammonium nitrate to inflate air bags. Tom Krisher, Detroit Free Press, "Ford says it will fight latest Takata airbag recall," 21 July 2017 Takata uses ammonium nitrate to create a small explosion that inflates air bags in a crash. Tom Krishner, USA TODAY, "Recalled Takata air bags showing up in used cars, lawsuit alleges," 22 Aug. 2017

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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Last Updated

4 Jan 2019

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Time Traveler for ammonium

The first known use of ammonium was in 1808

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am·​mo·​ni·​um | \ ə-ˈmō-nē-əm \

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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