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tin hat

American  

noun

Slang.

  1. a steel helmet worn by soldiers.

tin hat British  

noun

  1. obsolete a steel helmet worn by military personnel for protection against small metal fragments

"Collins English Dictionary — Complete & Unabridged" 2012 Digital Edition © William Collins Sons & Co. Ltd. 1979, 1986 © HarperCollins Publishers 1998, 2000, 2003, 2005, 2006, 2007, 2009, 2012

Etymology

Origin of tin hat

First recorded in 1915–20

Example Sentences

Examples are provided to illustrate real-world usage of words in context. Any opinions expressed do not reflect the views of Dictionary.com.

Diomande's act of foolishness just put the tin hat on it.

From BBC • Sep. 25, 2025

“I grabbed my tin hat and ran up to the poop deck and when everyone was up there we didn’t see any planes or anything, but a Liberty Ship near us was sinking,” Cribbs said.

From Washington Times • Nov. 2, 2014

The institutions that formed him, bade him don A tin hat at Suez, shimmer like elegant, gauzy backdrops Floating down from the flies.

From New York Times • Jul. 29, 2014

He might add a tin hat to accessorise with those natty stripy socks.

From The Guardian • Jan. 27, 2013

Gas mask, tin hat, ration coupons, and an umbrella.

From "Code Name Verity" by Elizabeth Wein

Definitions and idiom definitions from Dictionary.com Unabridged, based on the Random House Unabridged Dictionary, © Random House, Inc. 2023

Idioms from The American Heritage® Idioms Dictionary copyright © 2002, 2001, 1995 by Houghton Mifflin Harcourt Publishing Company. Published by Houghton Mifflin Harcourt Publishing Company.