noun, often attributive
fluo·​ride | \ ˈflȯr-ˌīd How to pronounce fluoride (audio) , ˈflu̇r- How to pronounce fluoride (audio) \

Definition of fluoride

1 : a compound of fluorine
2 : the monovalent anion of fluorine

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Examples of fluoride in a Sentence

Recent Examples on the Web In the May 2013 special election, when the highest profile ballot measure asked Portland voters whether fluoride should be added to the city’s drinking water, countywide turnout reached 28% as of the day before the Tuesday election. oregonlive, "Voter turnout for Portland City Council race between Dan Ryan, Loretta Smith at 32%," 11 Aug. 2020 This should include brushing regularly, flossing (or use interdental brushes or a water flosser), using a fluoride or chlorhexidine mouthwash and keeping a low sugar intake (as the harmful mouth bacteria feed on sugar). Katie Hunt, CNN, "Gum health could be a risk factor for dementia, study suggests," 29 July 2020 After the first phase, scheduled through next week, Chen will decide whether fluoride poses an unreasonable risk in drinking water. Bob Egelko, SFChronicle.com, "Trial underway in SF could remove fluoride from drinking water," 8 June 2020 About 200 million Americans, nearly two-thirds of the population, drink water containing fluoride to fight tooth decay. Bob Egelko, SFChronicle.com, "Trial underway in SF could remove fluoride from drinking water," 8 June 2020 Instead, prioritize brands that incorporate both natural ingredients and fluoride. Condé Nast Traveler, "The Best Natural Beauty Products for Your Dopp Kit," 30 Apr. 2020 West Manchester Township: Shiloh Water Authority has started the process to remove fluoride from the township’s water supply. USA TODAY, "MLK, robot unemployment, Python Bowl: News from around our 50 states," 14 Jan. 2020 The competitive existing product, Bite, has also left out fluoride. Caroline Delbert, Popular Mechanics, "Here's Your New Pretend Toothpaste," 19 Dec. 2019 In 1979, krill products were found to contain toothpaste-high quantities of fluoride, a compound that concentrates in krill shells, which further set back attempts to create a palatable krill cuisine. Lucy Jakub, Harper's magazine, "A View to a Krill," 2 Mar. 2020

These example sentences are selected automatically from various online news sources to reflect current usage of the word 'fluoride.' Views expressed in the examples do not represent the opinion of Merriam-Webster or its editors. Send us feedback.

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First Known Use of fluoride

1826, in the meaning defined at sense 1

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Time Traveler for fluoride

Time Traveler

The first known use of fluoride was in 1826

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Statistics for fluoride

Last Updated

22 Aug 2020

Cite this Entry

“Fluoride.” Merriam-Webster.com Dictionary, Merriam-Webster, https://www.merriam-webster.com/dictionary/fluoride. Accessed 19 Sep. 2020.

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More Definitions for fluoride


How to pronounce fluoride (audio) How to pronounce fluoride (audio)

English Language Learners Definition of fluoride

: a chemical that is sometimes added to drinking water and toothpaste to help keep teeth healthy


fluo·​ride | \ ˈflȯr-ˌīd How to pronounce fluoride (audio) , ˈflu̇r- \

Kids Definition of fluoride

: a compound of fluorine Many toothpastes contain fluoride to help prevent tooth decay.


flu·​o·​ride | \ ˈflu̇(-ə)r-ˌīd How to pronounce fluoride (audio) \

Medical Definition of fluoride

1 : a compound of fluorine with a more electropositive element or radical
2 : the monovalent anion of fluorine

Other Words from fluoride

fluoride adjective

More from Merriam-Webster on fluoride

Nglish: Translation of fluoride for Spanish Speakers

Britannica.com: Encyclopedia article about fluoride

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