[floo r-een, -in, flawr-, flohr-]
- the most reactive nonmetallic element, a pale-yellow, corrosive, toxic gas that occurs combined, especially in fluorite, cryolite, phosphate rock, and other minerals. Symbol: F; atomic weight: 18.9984; atomic number: 9.
Origin of fluorine
Dictionary.com Unabridged Based on the Random House Unabridged Dictionary, © Random House, Inc. 2018
Examples from the Web for fluorine
Oxygen will combine with iron or lead or sodium, but cannot be made to combine with fluorine.The Machinery of the Universe
Amos Emerson Dolbear
Their pseudo-flesh is composed mainly of silicon and fluorine.Masters of Space
Edward Elmer Smith
From this it will be understood that the fluorine will be evolved when the stone is fused.
Iodine, Fluorine, &c. had not been discovered at this period.The Life of Sir Humphrey Davy, Bart. LL.D., Volume 1 (of 2)
John Ayrton Paris
It is ready to unite with every known substance, fluorine excepted.Curiosities of Heat
Lyman B. Tefft
- 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
Word Origin and History for fluorine
Online Etymology Dictionary, © 2010 Douglas Harper
fluorine(flur′ēn′, -ĭn, flôr′-)
- A highly corrosive, toxic, gaseous halogen element. It is a component of many drugs, and its radioisotope is used in functional brain imaging and bone scans. Atomic number 9.
The American Heritage® Stedman's Medical Dictionary Copyright © 2002, 2001, 1995 by Houghton Mifflin Company. Published by Houghton Mifflin Company.
- 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. See Periodic Table.
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