tinfoil

[tin-foil]

noun

1. tin, or an alloy of tin and lead, in the form of a thin sheet, much used as a wrapping for drugs, foods, tobacco, etc.

tinfoil

/ ˈtɪnˌfɔɪl /

noun

1. thin foil made of tin or an alloy of tin and lead

2. thin foil made of aluminium; used for wrapping foodstuffs

Word History and Origins

Origin of tinfoil¹

First recorded in 1425–75, tinfoil is from the late Middle English word tynfoile. See tin, foil ²

Example Sentences

One suspect had an expensive phone wrapped in tinfoil in an attempt to block the device's signal and avoid it being traced.

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Every weekday morning, drivers arrive at the Little Tokyo Towers at 10 a.m. carrying precious cargo: seniors’ meals individually wrapped in tinfoil.

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The bodies of the two boys and two girls, likely born many years ago, were found in shoe boxes wrapped in tinfoil in November 2022.

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“I said, you know, I may sound like a crazy, tinfoil hat–wearing person,” Russo, also a veterinarian, recalled at a 5 April public talk sponsored by her company.

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“I feel like if I raise those concerns, they want to put a tinfoil hat on me and they want to say I’m an anarchist or an insurrectionist,” Crye said.

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When To Use

What is a tinfoil hat?

Tinfoil hat is a shorthand for saying someone believes in conspiracy theories, is paranoid, or is crazy more generally.