fluoride

American  

[floor-ahyd, flawr-, flohr-] / ˈflʊər aɪd, ˈflɔr-, ˈfloʊr- /

noun

Chemistry.

• fluorides
  plural

1. a salt of hydrofluoric acid consisting of two elements, one of which is fluorine, as sodium fluoride, NaF.

2. a compound containing fluorine, as methyl fluoride, CH 3 F.

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fluoride British  

/ ˈflʊəˌraɪd /

noun

1. any salt of hydrofluoric acid, containing the fluoride ion, F ^–

2. any compound containing fluorine, such as methyl fluoride

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fluoride Scientific  

/ flr′īd′ /

1. A compound containing fluorine and another element or radical. Fluorine combines readily with nearly all the other elements, except the noble gases, to form fluorides. In some countries, fluoride is added to the drinking water as a preventive measure against tooth decay.

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fluoride Cultural  

1. Any of a number of naturally occurring compounds of the element fluorine. Fluorides have been found to be effective in preventing tooth decay and are routinely added to drinking water in most jurisdictions.

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Other Word Forms

Noun Inflected Forms

• fluorides
  plural

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Etymology

Origin of fluoride

First recorded in 1820–30; fluor- + -ide ( def. )

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Compare meaning

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

• fluorine vs. fluoride

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Explanation

Fluoride is that ingredient in toothpaste that keeps tooth enamel strong and helps prevent cavities. Small amounts of fluoride are also present in tap water and certain foods and beverages. Fluoride is a naturally occurring mineral widely recognized for its oral health benefits. Fluoride is often added to toothpaste and mouthwash to help prevent tooth decay by making the enamel more resistant to acid attacks from bacteria and sugars. That’s why some communities add it to their water supply systems: Regular exposure to fluoride is generally considered important in maintaining oral hygiene. Fluoride is also found in tea, seafood, and some fruits and vegetables. Now that’s toothsome!

Example Sentences

See Examples For:

fluoride fluorides

Together, these capabilities make lithium fluoride detectors a promising tool for studying the complex radiation environment beyond Earth.

From Science Daily ● Oct. 28, 2026

The results showed that a solution containing 38% silver diamine fluoride successfully stopped decay in more than half of the affected baby teeth when treatment was provided at six month intervals.

From Science Daily ● Oct. 26, 2026

When thermal runaway starts, the process can continue for days, with the potential for batteries to release toxic gases such as hydrogen fluoride, hydrogen chloride and carbon monoxide.

From Los Angeles Times ● Sep. 25, 2026

In the case of large, multiple-battery fires, they can burn for days, while releasing toxic gases such as hydrogen fluoride, hydrogen chloride, carbon monoxide and carbon dioxide.

From Los Angeles Times ● Sep. 22, 2026

It is true that Washington lost most of his own teeth, which was hardly unusual in the days before modern dentists and fluoride toothpaste.

From "In the Shadow of Liberty" by Kenneth C. Davis

The Moffitt research team wanted to develop a more efficient process to create sulfoximines, sulfonimidoyl fluorides and sulfonimidamides.

From Science Daily ● Jan. 22, 2024

Fluorine will combine with oxygen to form fluorides such as OF2, where the oxygen has a 2+-oxidation state.

From Textbooks ● Feb. 14, 2019

Such wastes as chlorides, chlorates, salts of phosphonic acid, fluorides, and arsenic had been discharged from the Rocky Mountain Arsenal during the years of its operation by the Army Chemical Corps.

From The New Yorker ● Jan. 3, 2017

In the years since, fluorides have been proved to reduce the rate of tooth decay in adults as well as in children.

From New York Times ● Jan. 23, 2012

Chlorides, chlorates, salts of phosphonic acid, fluorides, and arsenic had been discharged from the Rocky Mountain Arsenal into holding ponds during the years of its operation.

From "Silent Spring" by Rachel Carson

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