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

Officers confiscated 74 pounds of cannabis products, 40 pounds of psilocybin mushrooms and 426 canisters of nitrous oxide, authorities said. —Caelyn Pender, Mercury News, 12 Aug. 2025

Investigators also reportedly found several bottles of nitrous oxide — which Podgorski noted is sometimes abused through inhalation. —Justin Muszynski, Hartford Courant, 4 Aug. 2025

In 2009, the finding gave the EPA authority to regulate six greenhouse gases — including carbon dioxide, methane and nitrous oxide — as threats to human health. —Sophie Hartley, IndyStar, 29 July 2025

Reducing potent agriculture emissions More food companies are starting to capitalize on the advantages of limiting two types of agricultural pollution common in their supply chains – methane and nitrous oxide. —Mindy Lubber, Forbes.com, 30 June 2025

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