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 
Example Sentences
Recent Examples on the Web Vitamin D is a fat-soluble vitamin essential for many bodily functions including strengthening the bones, supporting cell growth and regulation, retaining and absorbing calcium and phosphorus, and improving immunity. 
Valerie Agyeman, Good Housekeeping, 1 Sep. 2022 Excess nutrients—mainly nitrogen and phosphorus from sewage and agricultural runoff—are among the biggest detriments to water quality. Katherine Rapin, WIRED, 27 Aug. 2022 The typical recipe for a bloom also includes lots of nutrients, such as nitrogen and phosphorus, largely from agricultural practices. Caitlin Looby, Journal Sentinel, 12 Aug. 2022 The release of excess nutrients such as nitrogen and phosphorus, both found in sewage, can cause excess algae growth in bodies of water, which starves it of oxygen and can kill marine life. Christine Condon, Washington Post, 30 July 2022 Vitamin D is needed by the body to fully absorb calcium and phosphorus from food. Sandee Lamotte, CNN, 27 July 2022 The release of excessive nutrients like nitrogen and phosphorus, both found in sewage, can cause excess algae growth in bodies of water, which starves it of oxygen and can kill marine life. Christine Condon, Baltimore Sun, 27 July 2022 After all, vitamin D does help absorb and maintain adequate levels of calcium and phosphorus, which are key components of bone. Bruce Y. Lee, Forbes, 10 July 2022 Because two elements that were found in the coprolite (calcium and phosphorus) are indicative of meat consumption, the researchers concluded that the animal that produced the sample was a carnivore. Jeanne Timmons, Ars Technica, 6 June 2022 See More
Valerie Agyeman, Good Housekeeping, 1 Sep. 2022 Excess nutrients—mainly nitrogen and phosphorus from sewage and agricultural runoff—are among the biggest detriments to water quality. Katherine Rapin, WIRED, 27 Aug. 2022 The typical recipe for a bloom also includes lots of nutrients, such as nitrogen and phosphorus, largely from agricultural practices. Caitlin Looby, Journal Sentinel, 12 Aug. 2022 The release of excess nutrients such as nitrogen and phosphorus, both found in sewage, can cause excess algae growth in bodies of water, which starves it of oxygen and can kill marine life. Christine Condon, Washington Post, 30 July 2022 Vitamin D is needed by the body to fully absorb calcium and phosphorus from food. Sandee Lamotte, CNN, 27 July 2022 The release of excessive nutrients like nitrogen and phosphorus, both found in sewage, can cause excess algae growth in bodies of water, which starves it of oxygen and can kill marine life. Christine Condon, Baltimore Sun, 27 July 2022 After all, vitamin D does help absorb and maintain adequate levels of calcium and phosphorus, which are key components of bone. Bruce Y. Lee, Forbes, 10 July 2022 Because two elements that were found in the coprolite (calcium and phosphorus) are indicative of meat consumption, the researchers concluded that the animal that produced the sample was a carnivore. Jeanne Timmons, Ars Technica, 6 June 2022 See More 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-fə-rəs
: a white or yellowish waxy chemical element that gives a faint glow in moist air
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