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

Legumes Legumes, which include chickpeas, edamame, and black beans, are packed with magnesium, fiber, B vitamins, iron, copper, zinc, and phosphorus. —Audrey Noble, Vogue, 24 Oct. 2024

In 2022, the basin received a C- grade from Milwaukee Riverkeeper, including an F for phosphorus, a pollutant found in fertilizers. —Madeline Heim, Journal Sentinel, 23 Oct. 2024

That’s water plus the chemical elements for life — carbon, hydrogen, nitrogen, oxygen, sulfur and phosphorus. —Jamie Carter, Forbes, 13 Oct. 2024

White phosphorus is a waxy substance that ignites instantly when exposed to oxygen. —Courtney Kube, NBC News, 25 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