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

More Biology and Tech The e-tattoo is built from the thermoplastic polyvinylidene fluoride and graphene, which is an allotrope of carbon that's 100 times stronger than steel. Daisy Hernandez, Popular Mechanics, "A Soft Skin 'E-Tattoo' Might Just Save Your Life," 26 June 2019 To turn the adhesive off, Phillips and Kim applied fluoride to the edges of two microscopic glass slides stuck together, and the glass slides fell apart within minutes. Xiaozhi Lim, The Seattle Times, "Chemists in search of their Holy Grail: a plastic designed to die," 6 Aug. 2018 The big concern here is fluoride, the researchers said. Korin Miller, SELF, "Kids Are Using Too Much Toothpaste and It's Actually a Problem," 5 Feb. 2019 Too much fluoride can also cause discoloration and pitting, a condition known as dental fluorosis, the CDC says. Korin Miller, SELF, "Kids Are Using Too Much Toothpaste and It's Actually a Problem," 5 Feb. 2019 Joan talks to Jayme about sealants, fluoride, and enamel and tells her about a dental office that provides free cleanings to kids under 6. Tracy Saelinger, Woman's Day, "This Nurse Helps New Moms When They're Most Vulnerable," 8 Jan. 2019 Deeper, intrinsic stains are dark coloring that comes from within the tooth, sometimes as a result of trauma, weak enamel, certain types of medication, and even overuse of fluoride. Alexandra Tunell, Harper's BAZAAR, "Is Charcoal Toothpaste Safe to Use?," 9 Aug. 2017 According to Kibildis, the culprit ingredients that could be causing pimples incude baking soda, hydrogen peroxide, fluoride, sodium lauryl sulfate, alcohol, essential oils and menthol. Alexandra Tunell, Harper's BAZAAR, "5 Surprising Reasons You Have Acne," 26 June 2015 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

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

24 Jul 2019

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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 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

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More from Merriam-Webster on fluoride

Rhyming Dictionary: Words that rhyme with fluoride

Spanish Central: Translation of fluoride

Nglish: Translation of fluoride for Spanish Speakers

Britannica.com: Encyclopedia article about fluoride

Comments on fluoride

What made you want to look up fluoride? Please tell us where you read or heard it (including the quote, if possible).


a haphazard or makeshift solution

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