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.
Lithium iron phosphate batteries Lithium iron phosphate, or LFP, is already used in mass-market EVs and grid storage systems. — Atharva Gosavi, Interesting Engineering, 7 Nov. 2026 One example is phytase, which can release phosphate from phytate, a form of phosphorus found in organic matter. — Rafael De Toledo, MSNBC Newsweek, 6 Nov. 2026 Jackery announced a new portable power station that uses the safer and longer-lasting lithium iron phosphate (LFP) batteries the company first introduced in 2023. — Andrew Liszewski, The Verge, 2 Nov. 2026 Numata proposed that phosphate in the ampulla, the middle section of a spider’s silk glands, might initiate these interactions. — Yasemin Saplakoglu, Quanta Magazine, 28 Oct. 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

Browse Nearby Words

Cite this Entry

“Phosphate.” Merriam-Webster.com Dictionary, Merriam-Webster, https://www.merriam-webster.com/dictionary/phosphate. Accessed 9 Nov. 2026.

Kids Definition

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

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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