phosphate

noun

phos·​phate ˈfäs-ˌfāt How to pronounce phosphate (audio)
1
a(1)
: a salt or ester of a phosphoric acid
(2)
: the trivalent anion PO43− derived from phosphoric acid H3PO4
b
: an organic compound of phosphoric acid in which the acid group is bound to nitrogen or a carboxyl group in a way that permits useful energy to be released (as in metabolism)
2
: an effervescent drink of carbonated water with a small amount of phosphoric acid flavored with fruit syrup
3
: a phosphatic material used for fertilizers

Examples of phosphate in a Sentence

Recent Examples on the Web
Examples are automatically compiled from online sources to show current usage. Read More Opinions expressed in the examples do not represent those of Merriam-Webster or its editors. Send us feedback.
One pack, two chemistries In regions such as Xinjiang, where winter temperatures can fall below -25°C, lithium iron phosphate batteries can experience slower charging and significant capacity losses. Neetika Walter, Interesting Engineering, 8 June 2026 The system, which is based on a high-capacity lithium iron phosphate (LFP) battery with a capacity of 30 to 85 kWh, can sustain 7 to 14 days of complete off-grid living. Connie Etemadi, USA Today, 4 June 2026 For the better part of the 1900s, a regular pastime for kids and their parents was to head to the neighborhood drugstore for an egg cream, phosphate soda, or milkshake. Margaret Littman, Southern Living, 2 June 2026 Both have some of the world's richest deposits of potash and phosphate. Ariel Cohen, Forbes.com, 28 May 2026 See All Example Sentences for phosphate

Word History

Etymology

French, from acide phosphorique phosphoric acid

First Known Use

1788, in the meaning defined at sense 1a(1)

Time Traveler
The first known use of phosphate was in 1788

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Cite this Entry

“Phosphate.” Merriam-Webster.com Dictionary, Merriam-Webster, https://www.merriam-webster.com/dictionary/phosphate. Accessed 11 Jun. 2026.

Kids Definition

phosphate

noun
phos·​phate ˈfäs-ˌfāt How to pronounce phosphate (audio)
1
: a salt of a phosphoric acid
2
: a drink made of carbonated water and fruit syrup with a little phosphoric acid added for tang

Medical Definition

phosphate

noun
phos·​phate ˈfäs-ˌfāt How to pronounce phosphate (audio)
1
a
: a salt or ester of a phosphoric acid
b
: the trivalent anion PO43− derived from phosphoric acid H3PO4
2
: an organic compound of phosphoric acid in which the acid group is bound to nitrogen or a carboxyl group in a way that permits useful energy to be released (as in metabolism)

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