nitrous oxide

noun

: a colorless gas N₂O that when inhaled produces loss of sensibility to pain preceded by exhilaration and sometimes laughter, that is used especially as an anesthetic in dentistry and as a fuel, and that is an atmospheric pollutant and greenhouse gas produced by combustion

called also laughing gas

compare nitric oxide

Examples of nitrous oxide in a Sentence

Recent Examples on the Web

In a statement given to the The Athletic on Wednesday, Hampshire Police confirmed that Sterling had been charged with dangerous driving, possession of nitrous oxide for wrongful inhalation and failing to provide a specimen. — Jessica Hopkins, New York Times, 26 Aug. 2026

Traditional wool LCAs tally greenhouse gases, including methane from sheep digestion and nitrous oxide from manure and urine. — Alexandra Harrell, Footwear News, 21 Aug. 2026

The Texas State Board of Dental Examiners later wrote that Hemphill failed to account for the way Demerol would interact with nitrous oxide gas and two other sedation drugs. — Lillie Davidson, Fort Worth Star-Telegram, 20 Aug. 2026

Other microbes seemed to produce their own dark oxygen, perhaps to extract energy from hydrocarbons such as methane, much as drag racers inject nitrous oxide into their engines to boost horsepower. — James Dinneen, New Yorker, 13 Aug. 2026

Word History

First Known Use

1798, in the meaning defined above

Rhymes for nitrous oxide

• acetamide
• acetonide
• acidified
• antimonide
• beatified
• benzaldehyde
• borohydride
• chalcogenide
• commodified
• decalcified
• declassified
• disaccharide

Kids Definition

nitrous oxide

noun

: a colorless gas that when inhaled causes loss of the ability to feel pain and sometimes produces laughter and is used especially in dentistry

called also laughing gas

Medical Definition

nitrous oxide

noun

: a colorless gas N₂O that when inhaled produces loss of sensibility to pain preceded by exhilaration and sometimes laughter and is used especially as an anesthetic in dentistry

called also laughing gas