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Synonyms

laughing gas

American  

laughing gas British  

noun

  1. another name for nitrous oxide

"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

laughing gas Scientific  
/ lăfĭng /
  1. Nitrous oxide used as a mild anesthetic.


Etymology

Origin of laughing gas

First recorded in 1835–45

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.

The centers are also adding nitrous oxide, or laughing gas, for intrauterine device insertions.

From The Wall Street Journal • Mar. 1, 2026

Nitrous oxide – known colloquially as "laughing gas" – has many uses, from a painkiller during dental procedures to a whipping agent for canned whipped cream.

From BBC • May 27, 2025

Eutrophication and acidification are some of the environmental problems that can be traced to the use of ammonia -- as well as emissions of laughing gas, which is a very potent greenhouse gas.

From Science Daily • Feb. 5, 2024

It’s a little like “Mad Max” on laughing gas.

From New York Times • Jul. 20, 2023

The aroma was like laughing gas in the dentist’s chair—it made everything else go away.

From "The Lightning Thief" by Rick Riordan