mustard gas

noun

: an irritant vesicant oily liquid C4H8Cl2S used especially as a chemical weapon

Examples of mustard gas in a Sentence

Recent Examples on the Web
Examples are automatically compiled from online sources to show current usage. Read More Opinions expressed in the examples do not represent those of Merriam-Webster or its editors. Send us feedback.
Within his first year at the front, Malaparte was exposed to mustard gas, leaving a pulmonary lesion that, nearly forty years later, contributed to his death. — Thomas Meaney, New Yorker, 2 July 2025 In response, the German Army developed deadly chlorine and mustard gases. — Emilie Le Beau Lucchesi, Discover Magazine, 17 July 2025 Earlier this year, the organization also determined that the Islamic State group used mustard gas in an attack on the town of Marea. — Thomas G. Moukawsher, Newsweek, 13 Dec. 2024 The chemicals, including sarin, mustard gas and chlorine gas, represent a major test for Syria’s caretaker government. — Natasha Frost, New York Times, 7 Apr. 2025 See All Example Sentences for mustard gas

Word History

First Known Use

1917, in the meaning defined above

Time Traveler
The first known use of mustard gas was in 1917

Rhymes for mustard gas

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Browse Nearby Words

mustard family
mustard gas
mustard gold
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Cite this Entry

“Mustard gas.” Merriam-Webster.com Dictionary, Merriam-Webster, https://www.merriam-webster.com/dictionary/mustard%20gas. Accessed 7 Jul. 2026.

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Kids Definition

mustard gas

noun
: a poisonous gas used in war that has strongly irritating and especially blistering effects

Medical Definition

mustard gas

noun
: an irritant oily liquid C4H8Cl2S used especially as a chemical weapon that causes blistering, attacks the eyes and lungs, and is a systemic poison

called also dichlorethyl sulfide, sulfur mustard

More from Merriam-Webster on mustard gas

Britannica.com: Encyclopedia article about mustard gas

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