fluoride

noun

fluo·​ride ˈflȯr-ˌīd How to pronounce fluoride (audio) ˈflu̇r- How to pronounce fluoride (audio)
often attributive
1
: a compound of fluorine
2
: the monovalent anion of fluorine

Examples of fluoride in a Sentence

Recent Examples on the Web
Examples are automatically compiled from online sources to show current usage. Read More Opinions expressed in the examples do not represent those of Merriam-Webster or its editors. Send us feedback.
That’s the idea behind familiar ingredients like fluoride, as well as newer formulas built around calcium, phosphate or hydroxyapatite. — Ryan Brennan, Fort Worth Star-Telegram, 20 Oct. 2026 Most enamel-repair products rely on remineralization, which puts minerals back into weakened enamel using ingredients like fluoride, calcium, phosphate or hydroxyapatite. — Ryan Brennan, Miami Herald, 20 Oct. 2026 Fluorine is then released into the water as fluoride ions, while hydroxyl radicals and hydroxide ions help sever carbon-carbon bonds in the remaining molecular chains. — Alexandra Harrell, Footwear News, 14 Oct. 2026 For people whose dry mouth stems from a medical condition or medication, dentists often recommend an alcohol-free rinse with fluoride instead. — Hanna Wickes, Sacbee.com, 5 Oct. 2026 See All Example Sentences for fluoride

Word History

First Known Use

1826, in the meaning defined at sense 1

Time Traveler
The first known use of fluoride was in 1826

Phrases Containing fluoride

Rhymes for fluoride

See All Rhymes for fluoride

Browse Nearby Words

fluoridation
fluoride
fluoridization
See all Nearby Words

Cite this Entry

“Fluoride.” Merriam-Webster.com Dictionary, Merriam-Webster, https://www.merriam-webster.com/dictionary/fluoride. Accessed 27 Oct. 2026.

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Kids Definition

fluoride

noun
flu·​o·​ride
ˈflu̇(-ə)r-ˌīd
: a compound of fluorine with another element or chemical group

Medical Definition

fluoride

noun
flu·​o·​ride ˈflu̇(-ə)r-ˌīd How to pronounce fluoride (audio)
1
: a compound of fluorine with a more electropositive element or radical
2
: the monovalent anion of fluorine
fluoride adjective

More from Merriam-Webster on fluoride

Britannica.com: Encyclopedia article about fluoride

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