nitrous

Etymology

It is partly borrowed from Middle French nitreux and partly borrowed from Latin nitrōsus (“full of natron”),^[2][1] the Latin adjective being from nitrum (“natron”),^[3][4][5] which is from Ancient Greek νίτρον (nítron, “sodium carbonate, natron”),^[1] the source of nitre.^[3] The French word is recorded in Old French from the mid 13th century, in the phrase eau nitreuse, and in its specific chemical use from 1787.^[2] Merriam-Webster Unabridged takes it from New Latin,^[5] the Shorter Oxford as nitre with the suffix -ous.^[6] Middle English had the adjective nitrose (“bitter, sour”) from the same Latin word, in the early 15th century.^[7][3]

Earliest recorded meaning

Of the nature of nitre, or containing it: 1583, in Philip Barrough's Methode of Phisicke.^[2][5] Etymonline dates the word to about 1600,^[3] and Collins and the Oxford Dictionary of English to the 17th century.^[8][9]

Semantic evolution

The first sense was "of the nature of nitre", including the bitterness of nitre, a use now historical;^[2] Johnson (1755) defined it as impregnated with or consisting of nitre.^[10] From 1667, in Milton's Paradise Lost, to 1806 it meant mixed with nitre to form an explosive.^[2] The precise chemical sense, of compounds in which nitrogen has a lower valence than in the corresponding nitric ones, dates from the 1780s.^[3][2] Nitrous oxide, the anaesthetic gas, is recorded from 1799, in Humphry Davy;^[2] since 1977 the adjective alone has been a slang noun for that gas, used as a drug or in engines.^[2][5]

Timeline

• 1583 – of the nature of nitre; containing nitre.^[2][5]
• 1667 – mixed with nitre to form an explosive (obsolete by 1806).^[2]
• 1780s – in chemistry, containing nitrogen at a lower valence.^[3]
• 1977 – noun, slang, nitrous oxide.^[2][5]

Meanings

Adjective

1. Of, relating to or containing nitrogen, especially in compounds where it has a lower valence than in the corresponding nitric compounds: nitrous acid.^[5][8][2]
2. Of, relating to or containing nitre.^[5][2]

Noun

1. (informal) Nitrous oxide, used as a drug or to boost an engine.^[5][2]

Word family

• hyponitrous

Related words

• nitre
• nitric
• nitrogen
• nitroso
• natron

References

1. ^ a b c Wiktionary, the free dictionary, https://en.wiktionary.org
2. ^ a b c d e f g h i j k l m n Oxford English Dictionary Online (accessed March 2026), Oxford: Oxford University Press
3. ^ a b c d e f Harper, Douglas. Online Etymology Dictionary, https://www.etymonline.com
4. ^ Klein, Ernest. A Comprehensive Etymological Dictionary of the English Language. 2 vols. Amsterdam: Elsevier, 1966–1967.
5. ^ a b c d e f g h i Merriam-Webster Unabridged Dictionary (2024), online ed., Springfield, Mass.: Merriam-Webster
6. ^ Shorter Oxford English Dictionary on Historical Principles (2002), 5th ed., ed. William R. Trumble and Angus Stevenson, Oxford: Oxford University Press
7. ^ Kurath, Hans; Kuhn, Sherman M.; Lewis, Robert E., eds. (1952–2001), Middle English Dictionary, Ann Arbor: University of Michigan Press; online edition ed. Frances McSparran et al. (2000–2018)
8. ^ a b Collins English Dictionary (2023), Glasgow: HarperCollins
9. ^ Stevenson, Angus, ed. (2010), Oxford Dictionary of English, 3rd ed., Oxford: Oxford University Press
10. ^ Johnson, Samuel (1755), A Dictionary of the English Language, London; 4th ed. 1773; Johnson's Dictionary Online, ed. Beth Rapp Young et al.