fluorine

American  

[floor-een, -in, flawr-, flohr-] / ˈflʊər in, -ɪn, ˈflɔr-, ˈfloʊr- /

noun

Chemistry.

1. the most reactive nonmetallic element, a pale-yellow, corrosive, toxic gas that occurs combined, especially in fluorite, cryolite, phosphate rock, and other minerals. F; 18.9984; 9.

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fluorine British  

/ ˈflʊəriːn, ˈflʊərɪn /

noun

1. a toxic pungent pale yellow gas of the halogen group that is the most electronegative and reactive of all the elements, occurring principally in fluorspar and cryolite: used in the production of uranium, fluorocarbons, and other chemicals. Symbol: F; atomic no: 9; atomic wt: 18.9984032; valency: 1; density: 1.696 kg/m³; relative density: 1.108; freezing pt: –219.62°C; boiling pt: –188.13°C

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fluorine Scientific  

/ flr′ēn′ /

1. A pale-yellow, poisonous, gaseous element of the halogen group. It is highly corrosive and is used to separate certain isotopes of uranium and to make refrigerants and high-temperature plastics. It is also added in fluoride form to the water supply to prevent tooth decay. Atomic number 9; atomic weight 18.9984; melting point −223°C; boiling point −188.14°C; specific gravity of liquid 1.108 (at boiling point); valence 1.

2. See Periodic Table

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Etymology

Origin of fluorine

First recorded in 1805–15; fluor(ic) + -ine ¹

Compare meaning

How does fluorine compare to similar and commonly confused words? Explore the most common comparisons:

• fluorine vs. fluoride

Example Sentences

Fluorine is perhaps one of the most controversial elements on the periodic table.

From Salon • Aug. 27, 2024

Fluorine has killed, or tried to kill, every chemist who tried to isolate it.

From Nature • Sep. 1, 2020

Fluorine is the most powerful oxidizing agent of the known elements.

From Textbooks • Feb. 14, 2019

Fluorine does not form compounds in which it exhibits positive oxidation states; oxygen exhibits a positive oxidation state only when combined with fluorine.

From Textbooks • Feb. 14, 2019

Fluorine also exists in the enamel of the teeth, and in the bones of some animals.

From A System of Instruction in the Practical Use of the Blowpipe Being A Graduated Course Of Analysis For The Use Of Students And All Those Engaged In The Examination Of Metallic Combinations by Anonymous