noun, often attributive
phos·​pho·​rus | \ ˈfäs-f(ə-)rəs \

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 \ : a nonmetallic element of the nitrogen family that occurs widely especially as phosphates — see Chemical Elements Table

Examples of phosphorus in a Sentence

Recent Examples on the Web

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 Many of the chemicals used in fertilizer -- such as phosphorus and nitrogen -- reach the ocean via surface runoffs that occur after a rainstorm or hurricane. Madeline Farber, Fox News, "Dead whale shark in Florida washes up on beach; red tide likely killer," 27 July 2018 Bonemeal is a good source of phosphorus, and kelp or greensand are organic sources of potassium. The Editors Of Organic Life, Good Housekeeping, "Everything You Need To Know About Organic Fertilizer," 10 Mar. 2017 State environmental regulators set the limit for the amount of phosphorus coming into the lake, but the amount is regularly far more than the lake can handle. Jenny Staletovich, miamiherald, "Massive and toxic algae bloom threatens Florida coasts with another lost summer," 29 June 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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Last Updated

9 Feb 2019

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Time Traveler for phosphorus

The first known use of phosphorus was in 1680

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More Definitions for phosphorus



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 \

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 \

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

Comments on phosphorus

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a servile follower or underling

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