phosphate

American  

[fos-feyt] / ˈfɒs feɪt /

noun

1. Chemistry.

   1. (loosely) a salt or ester of phosphoric acid.

   2. a tertiary salt of orthophosphoric acid, as sodium phosphate.

2. Agriculture. a fertilizing material containing compounds of phosphorus.

3. a carbonated drink of water and fruit syrup containing a little phosphoric acid.

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phosphate British  

/ ˈfɒsfeɪt, fɒsˈfætɪk /

noun

1. any salt or ester of any phosphoric acid, esp a salt of orthophosphoric acid

2. (often plural) any of several chemical fertilizers containing phosphorous compounds

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phosphate Scientific  

/ fŏs′fāt′ /

1. A salt or ester of phosphoric acid, containing the group PO ₄. Phosphates are important in metabolism and are frequently used in fertilizers.

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Other Word Forms

• phosphatic adjective
• subphosphate noun

Etymology

Origin of phosphate

First recorded in 1785–95; phosph- + -ate ²

Example Sentences

Although the U.S. has a robust fertilizer manufacturing industry, the country still relies on nitrogen and phosphate imports to meet demand, Milam adds.

From Barron's • Mar. 29, 2026

The factory will produce lithium-iron phosphate cells for utility-scale batteries, which are in demand for AI data centers.

From The Wall Street Journal • Mar. 17, 2026

In a statement to USA Today, Costco explained that it uses carrageenan and sodium phosphate “to support moisture retention, texture, and product consistency during cooking,” adding that both ingredients are “approved by food safety authorities.”

From Salon • Feb. 26, 2026

Studies have linked excessive sodium phosphate intake to kidney strain and cardiovascular risks, and carrageenan to digestive inflammation and gut irritation.

From Los Angeles Times • Jan. 28, 2026

The charging of the battery, in which ADP and a free phosphate group are combined to restore ATP, is coupled to the oxidative process; the close linking is known as coupled phosphorylation.

From "Silent Spring" by Rachel Carson