fluo·​rine | \ ˈflu̇r-ˌēn How to pronounce fluorine (audio) , ˈflȯr- \

Definition of fluorine

: a nonmetallic gaseous chemical element of the halogen group with atomic number 9 that readily forms compounds with almost all other elements including some noble gases — see Chemical Elements Table

Examples of fluorine in a Sentence

Recent Examples on the Web For the block copolymer, the second block was a hydrocarbon with most of the hydrogens swapped out for fluorine atoms. John Timmer, Ars Technica, 6 July 2022 Initial tests showed that 54 of those products had measurable levels of total fluorine, indicating the presence of PFAS. Kathryn Rodgers, The Conversation, 4 May 2022 Combinations of carbon and fluorine molecules littered the soil and water, where they were absorbed by fish and, quite possibly, the people who live there. Kyle Bagenstose, USA TODAY, 7 Mar. 2022 In the 1970s, scientists began noticing that chlorine- and fluorine-containing chemicals in consumer products and refrigerants were eroding the ozone layer, leading to an uptick in solar radiation reaching the Earth’s surface. Nidhi Subbaraman, WSJ, 17 Mar. 2022 Other molecules cannot break between the carbon-fluorine bond, and instead slide off of surfaces treated with PFAS. Kyle Bagenstose, USA TODAY, 7 Mar. 2022 Heat is the key factor in breaking the carbon-fluorine bonds characteristic of this class of substances. Lars Fischer, Scientific American, 31 Jan. 2022 But the mystery of how fluorine was created within these stars has persisted. Ashley Strickland, CNN, 4 Nov. 2021 Finding fluorine in such a distant galaxy expands the reach of this element. Ashley Strickland, CNN, 4 Nov. 2021 See More

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.

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

Time Traveler

The first known use of fluorine was in 1813

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Dictionary Entries Near fluorine



fluorine test

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Statistics for fluorine

Last Updated

1 Aug 2022

Cite this Entry

“Fluorine.” Merriam-Webster.com Dictionary, Merriam-Webster, https://www.merriam-webster.com/dictionary/fluorine. Accessed 18 Aug. 2022.

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More Definitions for fluorine


fluo·​rine | \ ˈflu̇r-ˌēn How to pronounce fluorine (audio) , ˈflȯr- \

Kids Definition of fluorine

: a yellowish flammable irritating gaseous chemical element


fluo·​rine | \ ˈflu̇(-ə)r-ˌēn How to pronounce fluorine (audio) , -ən How to pronounce fluorine (audio) \

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

More from Merriam-Webster on fluorine

Nglish: Translation of fluorine for Spanish Speakers

Britannica.com: Encyclopedia article about fluorine


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