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 Danny recommends keeping the cotton/tinfoil combo on for 10-15 minutes and repeating as needed. Alexis Gaskin, Marie Claire, 22 Sep. 2021 When the eclipse begins, place the second piece of paper on the ground, and then hold your homemade projector — tinfoil side up — directly over it. BostonGlobe.com, 9 June 2021 Then put on your tinfoil helmet, lock yourself into your plexiglass cone of defiance, and hope for the best. Elena Kadvany, San Francisco Chronicle, 9 Aug. 2021 The menu encourages you to experiment with the possibilities, which come packaged neatly in a tinfoil box with a snickerdoodle cookie on the side. Andi Berlin, The Arizona Republic, 16 July 2021 The sun will shine through the small hole in the tinfoil and will be projected on the paper below. BostonGlobe.com, 9 June 2021 Before QAnon, there was that tinfoil-hat document called the Steele dossier. Kimberley A. Strassel, WSJ, 13 May 2021 Then again, with the draft only a few days away, who isn’t already wearing a tinfoil hat? Demetrio Teniente, Dallas News, 24 Apr. 2021 From his spot on the porch, Pimentel could see the tinfoil blocking the apartment windows to keep out the heat. Eli Saslow, Washington Post, 21 Mar. 2021

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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Dictionary Entries Near tinfoil

tin fish



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Statistics for tinfoil

Last Updated

25 Sep 2021

Cite this Entry

“Tinfoil.” Merriam-Webster.com Dictionary, Merriam-Webster, https://www.merriam-webster.com/dictionary/tinfoil. Accessed 19 Oct. 2021.

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More Definitions for tinfoil



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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