phosphorous

American  

[fos-fer-uhs, fos-fawr-uhs, -fohr-] / ˈfɒs fər əs, fɒsˈfɔr əs, -ˈfoʊr- /

adjective

Chemistry.

1. containing trivalent phosphorus.

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phosphorous British  

/ ˈfɒsfərəs /

adjective

1. of or containing phosphorus in the trivalent state

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Other Word Forms

• nonphosphorous adjective

Etymology

Origin of phosphorous

First recorded in 1770–80; phosphor- + -ous

Example Sentences

The report from environment groups Size of Wales and WWF Cymru says the soy is high in phosphorous, and becomes a pollutant when animal manure spread on land runs off into rivers.

From BBC • Nov. 9, 2025

Molasses is naturally rich in antioxidants, iron, calcium, magnesium, potassium, phosphorous and vitamin B6.

From Salon • Dec. 12, 2023

White phosphorous is considered an incendiary weapon under Protocol III of the Convention on the Prohibition of Use of Certain Conventional Weapons.

From Reuters • Oct. 12, 2023

Wastewater disposed in large bodies of water can result in high amounts of nitrogen and phosphorous, which can drive the growth of algae blooms.

From Los Angeles Times • Aug. 1, 2023

Each time, her hands were examined, judged clean, plunged into sealed boxes of dirt; and found to produce solid phosphorous granules.

From "American Spirits" by Barb Rosenstock