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

See Examples For:

sulfur dioxide

A Texas power station is a major producer of the pollutant sulfur dioxide.

From The Wall Street Journal ● May 23, 2026

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

From Salon ● May 10, 2026

The data revealed strong signatures of water, carbon dioxide, and sulfur dioxide, along with smaller amounts of methane.

From Science Daily ● May 7, 2026

The observations show that the planet's atmosphere is surprisingly dense and filled with heavier molecules, including water vapor, carbon dioxide, sulfur dioxide, and traces of methane.

From Science Daily ● May 7, 2026

“You’ve smelled rotten eggs? That’s sulfur dioxide, released from the chemical reaction of rotting organic material. This is going to stink just like that.”

From "October Sky" by Homer Hickam