tin·​foil | \ ˈtin-ˌfȯi(-ə)l How to pronounce tinfoil (audio) \

Definition of tinfoil

: a paper-thin metal sheeting usually of aluminum or tin-lead alloy

Examples of tinfoil in a Sentence

Wrap the leftover food in tinfoil.
Recent Examples on the Web Conspiracy theories flourished, from leftist filmmaker Michael Moore to the tinfoil hat-wearing Joy Reid of MSNBC, who tweeted questions about whether Trump really had the virus at all. John Kass, Star Tribune, "The virus that's killing America is our politics," 8 Oct. 2020 Thus our afternoon with the memory box, the playlist, the tinfoil boat. M. Boone Mattia, Washington Post, "A mother reflects on her long journey of reconsidering her child’s gender," 10 Sep. 2020 One of the main problems with conspiracy theories is that they are not confined to tinfoil-hat-wearing kooks or political extremists. Jovan Byford, CNN, "Covid-19 conspiracy theories: 6 tips on how to engage anti-vaxxers," 4 Aug. 2020 There's also no political risk for House Republican Conference Chairwoman Liz Cheney, Ohio Congressman Mike Turner and Florida Congressman Matt Gaetz to criticize McMurtry, who's challenging tinfoil hat-wearing U.S. Rep. Thomas Massie. Jason Williams, Cincinnati.com, "PX column: Bravo to GOP leaders for denouncing 'Hitler's Germany' comments. But why the Republican silence at other times?," 24 Apr. 2020 Swiss chocolate makers are offering unprecedented price cuts in an attempt to stem weak demand during the key Easter season, as shoppers scoop up toilet paper and canned soup rather than tinfoil bunnies. Corinne Gretler, Fortune, "Chocolatiers slash prices as shoppers in coronavirus lockdown buy toilet paper instead of Easter bunnies," 10 Apr. 2020 According to research done by MIT students in 2005, tinfoil can actually amplify mobile communication and satellite frequencies, including those used by the Federal Communication Commission. Joshua Pease, Popular Mechanics, "How You've Been Conditioned to Love Conspiracy Theories," 17 Dec. 2019 While waiting, officers found a homemade tinfoil pipe in the suspect’s vehicle. Joseph Clark, cleveland, "Fireworks to blame for loud gunshot-like sounds: Olmsted Falls Police Blotter," 30 Jan. 2020 Orion Sang, Detroit Free Press This story begins in Tokyo, of all places, where 30 years ago this February, Iron Mike Tyson took a fist to the face and folded like tinfoil. Rob Oller, Detroit Free Press, "How Ohio State took 'a punch to the face' to prepare for Michigan football," 24 Nov. 2019

These example sentences are selected automatically from various online news sources to reflect current usage of the word 'tinfoil.' 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 tinfoil

14th century, in the meaning defined above

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Time Traveler for tinfoil

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The first known use of tinfoil was in the 14th century

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Last Updated

18 Oct 2020

Cite this Entry

“Tinfoil.” Merriam-Webster.com Dictionary, Merriam-Webster, https://www.merriam-webster.com/dictionary/tinfoil. Accessed 21 Oct. 2020.

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More Definitions for tinfoil


How to pronounce tinfoil (audio)

English Language Learners Definition of tinfoil

: a thin sheet of shiny metal that is used especially for cooking or storing food


tin·​foil | \ ˈtin-ˌfȯil How to pronounce tinfoil (audio) \

Kids Definition of tinfoil

: a thin metal sheeting usually of aluminum or an alloy of tin and lead

More from Merriam-Webster on tinfoil

Nglish: Translation of tinfoil for Spanish Speakers

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