mustard gas

American  

noun

1. an oily liquid, C 4 H 8 Cl 2 S, used as a chemical-warfare gas, blistering the skin and damaging the lungs, often causing blindness and death: introduced by the Germans in World War I.

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mustard gas British  

noun

1. an oily liquid vesicant compound used in chemical warfare. Its vapour causes blindness and burns. Formula: (ClCH 2 CH 2 ) 2 S

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mustard gas Scientific  

/ mŭs′tərd /

1. An oily, volatile liquid that is corrosive to the skin and mucous membranes and causes severe, sometimes fatal respiratory damage. It was introduced in World War I as a chemical warfare agent. Chemical formula: C ₄ H ₈ Cl ₂ S.

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Etymology

Origin of mustard gas

First recorded in 1915–20; so called from its mustard-like odor

Example Sentences

The path to chemotherapy began with a 1943 wartime disaster in Bari, Italy, where sailors exposed to mustard gas showed severely depleted white blood cell counts.

From The Wall Street Journal • Apr. 24, 2026

In the world of Francesca May’s queer gothic fantasy “Wild and Wicked Things,” World War I was epoch-making not for its machine guns and mustard gas, but for its use of magic.

From Seattle Times • Jun. 10, 2022

Other substances and activities listed include HIV and cobalt, which were added in 2016, as well as tobacco smoking, solar radiation, mustard gas, and asbestos.

From Salon • Jan. 12, 2022

The poisoning of troops with mustard gas during World War I led to the production of chemotherapy.

From Scientific American • Apr. 27, 2021

Working with mustard gas, they found that this chemical produces permanent chromosome abnormalities that cannot be distinguished from those induced by radiation.

From "Silent Spring" by Rachel Carson

Related Words

• poison gas
• tear gas