foil(redirected from foils)
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Thin sheets of aluminum that are typically used to cover food and keep it fresh. Primarily heard in UK. Wrap those leftovers in silver foil so you can have them for lunch tomorrow.
slang A paranoid or delusional mindset centered around a belief in some conspiracy theory or another. Refers to the cliché of using such headgear to prevent mind-control or having one's thoughts read. A: "You know that they put those GPS trackers in your phones so the government can monitor you, right?" B: "Dude, you need to take your tinfoil hat off and spend some time away from the Internet for a while." A lot people wearing tinfoil hats believe the moon landing was faked by the US government.
See also: hat