hydrogen sulfide

American  

noun

1. a colorless, flammable, water-soluble, cumulatively poisonous gas, H 2 S, having the odor of rotten eggs: used chiefly in the manufacture of chemicals, in metallurgy, and as a reagent in laboratory analysis.

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hydrogen sulfide Scientific  

1. A colorless, poisonous gas that smells like rotten eggs. It is formed naturally by decaying organic matter and is the smelly component of intestinal gas. It is also emitted by volcanoes and fumaroles. Hydrogen sulfide is used in the petroleum, rubber, and mining industries, and in making sulfur. Chemical formula: H ₂ S.

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Etymology

Origin of hydrogen sulfide

First recorded in 1870–75

Example Sentences

Workers at Catalyst Refiners Inc. in Institute, W.Va., were cleaning and decontaminating a metal processing site—in preparation for closing it down—when a chemical reaction created dangerous hydrogen sulfide gas around 9:30 a.m.

From The Wall Street Journal • Apr. 22, 2026

Emissions of hydrogen sulfide raise health concerns in communities near California’s largest lake, researchers say.

From Los Angeles Times • Apr. 9, 2026

In 2021, the group found that CSE was not functioning properly in mice with Alzheimer's disease, and that very small injections of hydrogen sulfide helped protect brain function.

From Science Daily • Apr. 8, 2026

The air is rife with hydrogen sulfide, carrying the familiar smell of rotting eggs.

From Salon • Mar. 17, 2026

The first primitive forms of life consumed various materials, including hydrogen sulfide, and released oxygen.

From "A Brief History of Time: And Other Essays" by Stephen Hawking