sulphur dioxide

British

noun

Systematic name: sulphur(IV) oxide. a colourless soluble pungent gas produced by burning sulphur. It is both an oxidizing and a reducing agent and is used in the manufacture of sulphuric acid, the preservation of a wide range of foodstuffs ( E220 ), bleaching, and disinfecting. Formula: SO 2

"Collins English Dictionary — Complete & Unabridged" 2012 Digital Edition © William Collins Sons & Co. Ltd. 1979, 1986 © HarperCollins Publishers 1998, 2000, 2003, 2005, 2006, 2007, 2009, 2012

Example Sentences

Examples are provided to illustrate real-world usage of words in context. Any opinions expressed do not reflect the views of Dictionary.com.

Prior to 2020, dirty engine oil produced large amounts of sulphur dioxide, a gas harmful to human health.

From BBC • Oct. 17, 2025

The processing of phosphate rock into fertiliser emits toxic gases such as sulphur dioxide and ammonia.

From Barron's • Oct. 10, 2025

Nornickel said smelters in the Arctic city of Norilsk release roughly 1.8 million tonnes of sulphur dioxide emissions annually.

From Reuters • Oct. 25, 2023

This not only releases large amounts of CO2, but also produces toxic gases such as sulphur dioxide.

From Science Daily • Oct. 20, 2023

When a gaseous disinfectant is to be used sulphur dioxide or formaldehyde is employed, with the tendency lately to replace the former by the latter.

From The Home Medical Library, Volume V (of VI) by Winslow, Kenelm

Definitions and idiom definitions from Dictionary.com Unabridged, based on the Random House Unabridged Dictionary, © Random House, Inc. 2023