noun, often attributive
fluo·​ride | \ˈflȯr-ˌīd, ˈflu̇r- \

Definition of fluoride 

1 : a compound of fluorine

2 : the monovalent anion of fluorine

Examples of fluoride in a Sentence

Recent Examples on the Web

Considering toothpaste is essentially just a mix of alcohol, mint, fluoride, and detergents—i.e. Chloe Metzger, Marie Claire, "Does Toothpaste Make Your Boobs Bigger? An Investigation," 1 Aug. 2018 Free dental exams, screenings and fluoride varnish for children ages 2 to 17 will be available from the Palm Beach County Department of Health’s Mobile Children's Dental Health Unit at the seventh annual West Boca Community Dental Health Fair. Kari Barnett, Sun-Sentinel.com, "PBSO sponsors free dental services for children in West Boca," 11 July 2018 Some are concerned by harmless additives in tap water, such as disinfectants and fluoride, which effectively reduces tooth decay. Beth Mole, Ars Technica, "Meet “raw” water—ludicrously priced unfiltered water with random bacteria," 3 Jan. 2018 Tap water has all kinds of things in it that can affect your skin, such as fluoride, calcium, and magnesium. Dr. Leslie Baumann, miamiherald, "How to use a skin cleanser and see results," 3 July 2018 There was a medicinal flavor that reminded me of torturously swooshing my mouth with fluoride at the pediatric dentist. Alex Beggs, Bon Appetit, "I Ranked 14 Flavors of Emergen-C So You Don't Have to Wonder Anymore," 7 Mar. 2018 Hello Products’ Activate Charcoal toothpaste is also fluoride-free. Emma Sarran Webster, Teen Vogue, "Hello Products Activated Charcoal Fluoride Free Whitening Toothpaste Review," 5 Mar. 2018 Unfortunately, the medicine quickly disintegrates into a clear lump of glue, and you are forced to continuously reapply, shoving fistfuls of fluoride onto your face. Iman Hariri-kia, Teen Vogue, "What It Feels Like to Go on Accutane," 11 June 2018 But in this family, it's mainly caused by fluoride. Willi Evans Galloway, Good Housekeeping, "How To Grow Lucky Bamboo," 8 Apr. 2016

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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Statistics for fluoride

Last Updated

13 Nov 2018

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Time Traveler for fluoride

The first known use of fluoride was in 1826

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More Definitions for fluoride



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, 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 \

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

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Comments on fluoride

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