phosphorus

noun

phos·​pho·​rus ˈfäs-f(ə-)rəs 

often attributive

1

: a phosphorescent substance or body

especially : one that shines or glows in the dark

2

or less commonly phosphorous

ˈfäs-f(ə-)rəs 

: a nonmetallic element of the nitrogen family with atomic number 15 that occurs widely in combination especially as phosphates, that is essential for life in all known organisms, and that is used especially in fertilizers and organophosphorus compounds see Chemical Elements Table

Examples of phosphorus in a Sentence

Recent Examples on the Web

Their high content of phosphorus and calcium helps improve bone mineralization, which keeps bones strong long term. —Jeanne Ballion, Vogue, 31 Oct. 2024

The geologists estimate that S2 delivered 363 billion metric tons of phosphorus, a biological nutrient essential to life, into the oceans. —Margherita Bassi, Smithsonian Magazine, 25 Oct. 2024

The San Francisco Orchid Society recommends using a formula with low nitrogen and higher potassium and phosphorus (NPK 10-30-20). —Marin Independent Journal, The Mercury News, 9 Oct. 2024

This may include restricting sodium to less than 1,500 mg per day, avoiding alcohol, limiting foods high in potassium or phosphorus, and reducing your protein intake.9 4. —Kumkum S. Patel, Verywell Health, 26 Sep. 2024

Word History

Etymology

New Latin, from Greek phōsphoros light-bearing — more at phosphor

First Known Use

1680, in the meaning defined at sense 1

Kids Definition

phosphorus

noun

phos·​pho·​rus ˈfäs-f(ə-)rəs 

1

: a phosphorescent substance

especially : one that glows in the dark

2

: a nonmetallic element that occurs widely especially as phosphates see element

phosphoric

fäs-ˈfȯr-ik

-ˈfär-

adjective

phosphorous

ˈfäs-f(ə-)rəs;

fäs-ˈfōr-əs

-ˈfȯr-

adjective

Medical Definition

phosphorus

noun

phos·​pho·​rus ˈfäs-f(ə-)rəs 

often attributive

: a nonmetallic multivalent element that occurs widely in combined form especially as inorganic phosphates in minerals, soils, natural waters, bones, and teeth and as organic phosphates in all living cells and that exists in several allotropic forms

—symbol P see Chemical Elements Table