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

But the ports on the Red Sea weren’t built for phosphate trade.

From The Wall Street Journal • May 13, 2026

Unusually pure phosphate deposits -- a key ingredient in fertiliser -- once made Nauru one of the wealthiest places, per capita, on the planet.

From Barron's • May 13, 2026

Maaden erected prefabricated warehouses for the fertilizer and rigged piping systems to move corrosive sulfuric acid, a key ingredient in phosphate production, into stainless-steel tanker trucks.

From The Wall Street Journal • May 13, 2026

Mosaic is scaling back phosphate production at facilities in the U.S. and Brazil beginning this month as the company reassesses its operating plan for the rest of the year.

From Barron's • May 11, 2026

It is now known that many pairs of organic phosphate insecticides are highly dangerous, the toxicity being stepped up or “potentiated” through the combined action.

From "Silent Spring" by Rachel Carson