What does nitrous mean?
Nitrous is an adjective used primarily in the names of chemical compounds, especially nitrous oxide and nitrous acid. Nitrous oxide is a colorless gas that produces analgesic and sedative effects when inhaled, so it is used in medicine and dentistry; it also propels whipped cream from disposable dispensers. In informal contexts, the shortened form nitrous can refer to nitrous oxide itself, while the alternative name laughing gas emphasizes its tendency to cause relaxation, euphoria, and involuntary laughter. The adjective is also used in chemistry to distinguish compounds from related nitric compounds. Overall, nitrous is a technical word with a surprisingly familiar presence in healthcare, restaurants, and popular culture.
adjectiveDenoting or relating to oxides of nitrogen, especially nitrous oxide (N₂O), a colorless gas used as an anesthetic and food propellant; also denoting nitrous acid (HNO₂).
- Denoting or relating to nitrous oxide or another oxide of nitrogen, especially the colorless gas N₂O used as an anesthetic and as a propellant in whipped cream dispensers.
- Denoting nitrous acid, HNO₂, a weak inorganic acid.
"The dentist offered nitrous oxide to help the patient relax during the procedure."
"The dentist administered nitrous oxide while fitting the crown."
"The label identifies the active ingredient as a nitrous oxide mixture."
The gas that makes whipped cream fluffy has also been used to ease pain and send patients into relaxed, giggly states.
Reviewed by Deb Chak, Editor. AI-assisted content curated by RJS Tech Solutions LLP.
Where does nitrous come from?
Nitrous comes through English from the Latin adjective nitrosus, meaning “of or resembling natron” or “containing nitrates.” Latin nitrum, the source of nitrosus, was borrowed from Greek nitron, the ancient name for natron, a naturally occurring sodium carbonate used in glassmaking, soapmaking, and other processes. The related scientific words nitrogen, nitrate, nitrite, and nitric belong to the same etymological family.
Related word forms
How nitrous is actually used
In technical and formal contexts, nitrous commonly appears in the compounds nitrous oxide and nitrous acid. Informally, nitrous can stand alone for nitrous oxide, also called laughing gas; this usage may carry associations with medicine, dentistry, food preparation, or recreational use.
Easily confused with nitrous
Nitrous usually refers to compounds in which nitrogen has a lower oxidation state, while nitric refers to compounds such as nitric acid in which it has a higher oxidation state.