sulfur dioxide

American  

noun

Chemistry.

1. a colorless, nonflammable, water-soluble, suffocating gas, SO 2 , formed when sulfur burns: used chiefly in the manufacture of chemicals such as sulfuric acid, in preserving fruits and vegetables, and in bleaching, disinfecting, and fumigating.

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sulfur dioxide Scientific  

1. A colorless, poisonous gas or liquid with a strong odor. It is formed naturally by volcanic activity, and is a waste gas produced by burning coal and oil and by many industrial processes, such as smelting. It is also a hazardous air pollutant and a major contributor to acid rain. Chemical formula: SO ₂ .

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Etymology

Origin of sulfur dioxide

First recorded in 1865–70

Example Sentences

When an incoming ion strikes an oxygen-treated surface, two oxygen atoms can combine with a nearby sulfur atom to form sulfur dioxide, a stable gas that can naturally leave the surface.

From Science Daily • Jun. 17, 2026

Last year, Parish pumped out 36,000 tons of sulfur dioxide, 49% more than the prior year.

From The Wall Street Journal • May 21, 2026

That year, Parish emitted 42,689 tons of sulfur dioxide, about 16% more than last year.

From The Wall Street Journal • May 21, 2026

Freeport spent $250 million on improvements completed in 2017 to better control sulfur dioxide emissions.

From Salon • May 10, 2026

White deposits, including those around Prometheus, may be frozen sulfur dioxide.

From "Cosmos" by Carl Sagan