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trench knife

American  

noun

  1. a short knife for stabbing, sometimes equipped with brass knuckles as a guard, used in modern warfare in hand-to-hand combat.

trench knife British  

noun

  1. a double-edged steel knife, often with a guard in the form of a knuckle-duster, designed for close combat

"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 trench knife

First recorded in 1915–20

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.