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

The state has met 100% of its sediment reduction targets, but only 80% for nitrogen and 62% for phosphorus. —Karri Peifer, Axios, 16 Dec. 2024

People with certain types of kidney disease may be told to avoid phosphorus, so this cheese may be a better option.12 4. —Maxine Lipner, Verywell Health, 9 Dec. 2024

Because of some other things that happened in the tributaries to the Upper Klamath Lake, the phosphorus grew exponentially. —Dana Taylor, USA TODAY, 6 Dec. 2024

Much of the land was previously a large cornfield, and chemicals like phosphorus from fertilizer have degraded the water quality in the river. —Joseph Lee, Vox, 26 Nov. 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