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

Excess nitrogen increases nitrous oxide without a clear increase in crop yields and increases water pollution. —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

The potential impacts of abusing nitrous oxide cannot be overemphasized. —Katia Hetter, CNN Money, 15 May 2026

California law allows individuals 18 years and older to purchase nitrous oxide as long it is not inhaled after purchase. —City News Service, Daily News, 12 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