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.
After 15 years of experiments, Schumm’s group ended up with a recipe for solid calcium fluoride crystals, doped with little impurities of thorium 229, that looked like transparent millimeter-sized cubes. — Jacek Krywko, Scientific American, 20 Aug. 2026 Fluoride Keeps Working After You Brush For cavity protection, fluoride is one of the most important ingredients in toothpaste. — Md Published, Verywell Health, 11 Aug. 2026 These standards include safety guidelines, spell out who is eligible for Head Start and provide detailed rules — such as the requirement that kids in the program brush their teeth once daily with fluoride toothpaste. — Sequoia Carrillo, NPR, 6 Aug. 2026 This gives the fluoride extra time to do its job and provide better protection against decay. — Maggie Ryan, Flow Space, 23 July 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 1 Sep. 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

Last Updated: - Updated example sentences
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