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Synonyms

poison gas

American  

noun

  1. any of various toxic gases, especially those used in chemical warfare to kill or incapacitate on inhalation or contact, as phosgene, chlorine, etc.

poison gas British  

noun

  1. a gaseous substance, such as chlorine, phosgene, or lewisite, used in warfare to kill or harm

"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 poison gas

First recorded in 1910–15

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.

In Ankara, Siegfried became co-director of a gas mask factory, a joint Turkish-German enterprise next door to a poison gas laboratory.

From Los Angeles Times • Mar. 26, 2025

It concludes with a stanza describing the death of a fellow soldier following a poison gas attack:

From Salon • Jul. 9, 2023

A few paragraphs later, though, he concedes that “some are noxious,” listing slavery and poison gas as examples.

From Washington Post • Jun. 24, 2022

They said it had sent up a dangerous cloud of poison gas.

From Reuters • Apr. 5, 2022

It filled the hall like a poison gas.

From "Beowulf: A New Telling" by Robert Nye

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.