ammonium
noun
am·mo·ni·um
ə-ˈmō-nē-əm 
: 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
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There are a number of products on the market that contain essential oils, like clove or citrus, sodium or ammonium derivatives or even acetic acid (vinegar).
—
Dawn Pettinelli, Hartford Courant, 13 June 2026
Haji says that once the tungsten ore is mined, it is usually processed into a concentrate and shipped to a processor that turns it into ammonium paratungstate, or APT.
—Ari Sen, Scientific American, 13 June 2026
For example, adding too much fertilizer with ammonium, or NH4, can result in the soil becoming too acidic over time.
—Rae Ford, Martha Stewart, 7 June 2026
Feeding the orbs To test how LiPfe sustains itself, Jobson’s team exposed its explants to isotopically labeled amino acids and ammonium.
—Jacek Krywko, ArsTechnica, 29 May 2026
See All Example Sentences for ammonium
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Dawn Pettinelli, Hartford Courant, 13 June 2026
Haji says that once the tungsten ore is mined, it is usually processed into a concentrate and shipped to a processor that turns it into ammonium paratungstate, or APT.
—Ari Sen, Scientific American, 13 June 2026
For example, adding too much fertilizer with ammonium, or NH4, can result in the soil becoming too acidic over time.
—Rae Ford, Martha Stewart, 7 June 2026
Feeding the orbs To test how LiPfe sustains itself, Jobson’s team exposed its explants to isotopically labeled amino acids and ammonium.
—Jacek Krywko, ArsTechnica, 29 May 2026
See All Example Sentences for ammonium
Cite this Entry
“Ammonium.” Merriam-Webster.com Dictionary, Merriam-Webster, https://www.merriam-webster.com/dictionary/ammonium. Accessed 19 Jun. 2026.
Copy CitationKids Definition
ammonium
noun
am·mo·ni·um
ə-ˈmō-nē-əm
: an ion that comes from the combination of ammonia with a hydrogen ion
Medical Definition
ammonium
noun
am·mo·ni·um
ə-ˈmō-nē-əm
: 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
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