fluo·​rine | \ˈflu̇r-ˌēn, ˈflȯr-\

Definition of fluorine 

: a nonmetallic halogen element that is isolated as a pale yellowish flammable irritating toxic diatomic gas — see Chemical Elements Table

Examples of fluorine in a Sentence

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Here, uranium is reacted with fluorine to make uranium hexafluoride gas (UF6). Umair Irfan, Vox, "Uranium enrichment will be a key point in talks with North Korea. Here’s what it is.," 11 June 2018 From a perspective of science, the material is a clever mesh of silicates with a dash of fluorine secret sauce. Lee Hutchinson, Ars Technica, "The Internet-demanded, partially scientific testing of Ultra-Ever Dry (in HD!)," 4 July 2018 The gas is then pumped through membranes, the idea being that lighter isotopes of uranium would diffuse faster than heavier isotopes (fluorine has only one naturally occurring isotope, so any differences in the mass of the gas come from uranium). Umair Irfan, Vox, "Uranium enrichment will be a key point in talks with North Korea. Here’s what it is.," 11 June 2018 This is a chain of eight carbon atoms, seven of which have fluorine atoms attached to them; the eighth is linked to two oxygen atoms, typical of an organic acid. John Timmer, Ars Technica, "EPA boots reporters from meeting on chemicals called a PR disaster," 22 May 2018 At the core of these molecules is a carbon-fluorine bond that is extremely strong and resilient, qualities that end up in the finished substance. 3M used to make C8 for its Scotchgard products and also sold the chemical to DuPont for making Teflon. Ken Otterbourg, Fortune, "Teflon’s River of Fear," 24 May 2018 There are many variations of perfluorooctanoic acid that can be made by substituting for various fluorines, and many of these variants have found uses in the production of everything from non-stick cooking to fire-fighting foams. John Timmer, Ars Technica, "EPA boots reporters from meeting on chemicals called a PR disaster," 22 May 2018 By Halloween, that Sunday in 1948, 26 people had died due to inhalation of sulfuric acid, nitrogen dioxide, fluorine, and other poisonous gases. Dino Grandoni, Washington Post, "The Energy 202: Mining agency hopes you read its website to comment on deregulation," 2 Nov. 2017 The new model suggests our home planet contains significantly more sodium, potassium, chlorine, zinc, strontium, fluorine, gallium, rubidium, niobium, gadolinium, tantalum, helium, argon, and krypton than previously believed. Jay Bennett, Popular Mechanics, "Scientists Create Most Accurate Estimate of Earth's Composition," 18 Sep. 2017

These example sentences are selected automatically from various online news sources to reflect current usage of the word 'fluorine.' 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 fluorine

1813, in the meaning defined above

History and Etymology for fluorine

French, from New Latin fluor

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Time Traveler for fluorine

The first known use of fluorine was in 1813

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More Definitions for fluorine


fluo·​rine | \ˈflu̇r-ˌēn, ˈflȯr-\

Kids Definition of fluorine

: a yellowish flammable irritating gaseous chemical element


fluo·​rine | \ˈflu̇(-ə)r-ˌēn, -ən \

Medical Definition of fluorine 

: a nonmetallic monovalent halogen element that is normally a pale yellowish flammable irritating toxic gas symbol F — see Chemical Elements Table

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More from Merriam-Webster on fluorine

Rhyming Dictionary: Words that rhyme with fluorine

Spanish Central: Translation of fluorine

Nglish: Translation of fluorine for Spanish Speakers

Britannica.com: Encyclopedia article about fluorine

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