noun, often attributive
phos·​pho·​rus | \ ˈfäs-f(ə-)rəs How to pronounce phosphorus (audio) \

Definition of phosphorus

1 : a phosphorescent substance or body especially : one that shines or glows in the dark
2 or less commonly phosphorous \ ˈfäs-​f(ə-​)rəs How to pronounce phosphorous (audio) \ : 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

Government officials also showed CNN a handwritten manual detailing instructions for how to build incendiary weapons, including white phosphorus munitions, amongst other things. Sheena Mckenzie, Tamara Qiblawi And Fred Pleitgen, CNN, "Dozens suffocate in 'horrifying' suspected chemical attack in Syria," 8 Apr. 2018 The explosive ruptures drums or other containers while the phosphorus burns at high temperature, neutralizing the chemical agent. David Hambling, Popular Mechanics, "These Are Syria's Chemical Weapons. Here's How To Destroy Them," 13 Apr. 2018 Seaweed sequesters nitrogen, phosphorus, and carbon, meaning seaweed farms are carbon negative. Tamar Adler, Vogue, "Is Seaweed the Perfect Food?," 15 Feb. 2019 The American grenade section of the school of arms March 1, 1918, related that a very simple improvised smoke-bomb grenade could be constructed by filling a tennis ball with equal parts of red phosphorus and gun powder. Kyle Mizokami, Popular Mechanics, "Five Innovations to Emerge From the First World War," 11 Nov. 2018 Be sure to use organic fertilizer because the salts and high phosphorus concentrations often present in synthetic fertilizers can also cause tip burn. Willi Evans Galloway, Good Housekeeping, "How to Grow Extra-Lush Lucky Bamboo," 20 Aug. 2018 The sample burns in the flame, producing a light wave, the color of which is determined by the elements present, such as phosphorus. Popular Mechanics Editors, Popular Mechanics, "How the Experts Identify Chemical Weapons and Prove an Attack," 7 Aug. 2018 Australian researchers have made quantum computer components by precisely positioning phosphorus atoms on a silicon chip. Sophia Chen, WIRED, "Scientists Are Using AI to Painstakingly Assemble Single Atoms," 23 May 2018 Elements like phosphorus, nitrogen, and potassium could be salvaged from such waste. David Grossman, Popular Mechanics, "What If Animal Feces Could Be Recycled for Metals and Valuable Elements?," 29 Nov. 2018

These example sentences are selected automatically from various online news sources to reflect current usage of the word 'phosphorus.' Views expressed in the examples do not represent the opinion of Merriam-Webster or its editors. Send us feedback.

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First Known Use of phosphorus

1680, in the meaning defined at sense 1

History and Etymology for phosphorus

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

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18 May 2019

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Time Traveler for phosphorus

The first known use of phosphorus was in 1680

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English Language Learners Definition of phosphorus

chemistry : a poisonous chemical element that glows in the dark and burns when it is touched by air


phos·​pho·​rus | \ ˈfäs-fə-rəs How to pronounce phosphorus (audio) \

Kids Definition of phosphorus

: a white or yellowish waxy chemical element that gives a faint glow in moist air


noun, often attributive
phos·​pho·​rus | \ ˈfäs-f(ə-)rəs How to pronounce phosphorus (audio) \

Medical Definition of phosphorus

: 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

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More from Merriam-Webster on phosphorus

Spanish Central: Translation of phosphorus

Nglish: Translation of phosphorus for Spanish Speakers

Britannica English: Translation of phosphorus for Arabic Speakers Encyclopedia article about phosphorus

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