phos·​phate | \ˈfäs-ˌfāt \

Definition of phosphate 

1a(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

Mosaic currently runs its Florida phosphate operations from a multi-story office building in southeastern Hillsborough. Kevin Bouffard,, "Fortune 500 phosphate company Mosaic moving headquarters to Florida," 15 May 2018 The day after the meeting, Mr. Smotkin attended a conference sponsored by the OCP Policy Center, a think tank funded by the phosphate giant. New York Times, "A Lobbyist Helped Pruitt Plan a Morocco Trip. Then Morocco Hired the Lobbyist.," 1 May 2018 Current examples of value stocks within the S&P 500 include several in the energy sector, such as Baker Hughes , Loews Corp. and Mosaic Co. , which produces phosphates and potash. Mark Hulbert, WSJ, "‘Value’ Stocks May Not Be the Bear-Market Cure, After All," 8 July 2018 Beneath Florida’s crust lies a third of the world’s phosphate, the compressed residue of 25 million years of prehistoric creatures. Vincent Crampton,, "Explore Florida's Polk County: Reclaiming Florida at Streamsong Resort," 6 May 2018 Cotton lacking the gene pioneered at A&M got crowded out by the weeds in fields where the soil was fertilized with phosphate. Lynn Brezosky, San Antonio Express-News, "A&M cotton research could open new front in war on weeds," 5 July 2018 Genetech’s other flu drug, Tamiflu (oseltamivir phosphate), needs to be taken twice a day for five days within 48 hours of the onset of flu symptoms. Beth Mole, Ars Technica, "This novel, one-and-done flu drug could be available soon in the US," 27 June 2018 Lead from old pipes leached into the water supply because corrosion-reducing phosphates were not added due to an incorrect reading of federal regulations. Rebecca Bratek, CBS News, "Local sorority raises $20,000 to help Flint's water crisis," 14 June 2018 People with this genetic disease lack sufficient levels of phosphate, a mineral needed in bone formation, in their bodies. Shari Rudavsky, Indianapolis Star, "From lab to pharmacy: IU researchers' discovery leads to new drug to treat rare bone disease," 18 May 2018

These example sentences are selected automatically from various online news sources to reflect current usage of the word 'phosphate.' 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 phosphate

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

History and Etymology for phosphate

French, from acide phosphorique phosphoric acid

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Last Updated

5 Nov 2018

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The first known use of phosphate was in 1788

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English Language Learners Definition of phosphate

chemistry : a salt or compound that has phosphorus in it and that is used especially in products (called fertilizers) that help plants grow


phos·​phate | \ˈfäs-ˌfāt \

Medical Definition of phosphate 

1a : 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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More from Merriam-Webster on phosphate

Spanish Central: Translation of phosphate

Nglish: Translation of phosphate for Spanish Speakers

Britannica English: Translation of phosphate for Arabic Speakers Encyclopedia article about phosphate

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