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

The vehicle, which was recently purchased for racing, had a nitrous oxide system, officials said. —Jt Moodee Lockman, CBS News, 8 June 2026

Since 2001, the company has already flown three missions with a small spacecraft, Mira, which was first launched in 2023 with a novel propulsion system powered by non-toxic propellants, nitrous oxide and ethane. —Eric Berger, ArsTechnica, 2 June 2026

Use of synthetic nitrogen increased by about 76% after 2000, boosting nitrous oxide – another powerful greenhouse gas. —Hanqin Tian, Fortune, 25 May 2026

Rice paddies emit methane and nitrous oxide from wet or flooded soils. —Hanqin Tian, The Conversation, 22 May 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