nox

N1O1X8
/ɛn əʊ ˈɛks/

noun

The period of darkness in each twenty-four hours; a night.

“Near-synonym: nos”

Similar
Less commonScrabble 10

Meanings

nox1

nounnox (plural noctes or (deprecated) noxes or (proscribed) noces)

plural noctes · plural proscribed noxes · plural proscribed noces

  1. The period of darkness in each twenty-four hours; a night.

nox2

nounnox (plural nox)
  1. raremillilux (unit of illuminance)

nox3

nounnox (uncountable)
  1. alternativeuncountableAlternative form of NOx (nitrogen oxides)
  2. abbreviationuncountableAbbreviation of nitrous oxide (“N₂O”).

    Near-synonym: nos

    Synonyms: nos, nos

Nox4

proper noun
  1. Romanhuman sciencesThe Roman goddess of night.

NOx5

nounNOₓ
  1. chemistryAny of the various nitrogen oxides produced during combustion.

    "The NOx and particulate reductions provide clean air in the cities and communities we serve. [...]"

    2020 December 16, Daniel Puddicombe, “Treated DMUs become greener and cleaner”, in Rail, page 46

NOx6

nounNOx (uncountable)
  1. alternativeuncountableautomotive performanceAlternative form of nox (“nitrous oxide”).

Synonyms & antonyms

Origin

nox · noun

  1. Proto-Indo-European*nókʷts
  2. Proto-Italic*nok⁽ʷ⁾ts
  3. Latinnox
  4. Englishnox

Learned borrowing from Latin nox, from Proto-Italic *nok⁽ʷ⁾ts, from Proto-Indo-European *nókʷts.

Full word history & related roots →

nox · noun

  1. Latinnox“night; darkness”
  2. Englishnox

From Latin nox (“night; darkness”), by analogy with lux from Latin lūx (“light; daylight, day”). Doublet of night.

Full word history & related roots →

nox · noun

From N (“nitrogen”) + ox (“oxide”).

Full word history & related roots →

Nox · proper noun

  1. LatinNox
  2. LatinNox
  3. EnglishNox

Borrowed from Latin Nox.

Full word history & related roots →

NOx · noun

From N (“nitrogen”) + O (“oxygen”) + x (“x substitution value”).

Full word history & related roots →

NOx · noun

From N (“nitrous”) + Ox (“oxygen”).

Full word history & related roots →

Translations

Hungarian nitrózus gázok, nitrózus gáz
  • nitrózus gázoknitrogen oxides
  • nitrózus gáznitrogen oxides
Korean 녹스
  • 녹스 (nokseu)nitrogen oxides

Rhymes & wordplay

Anagrams

Cite this entry
APA

nox. (n.d.). In WatkinsX Dictionary. Retrieved November 2, 2026, from https://dictionary.watkinsx.com/word/nox

MLA

“nox.” WatkinsX Dictionary, https://dictionary.watkinsx.com/word/nox. Accessed November 2, 2026.

Chicago

WatkinsX Dictionary, s.v. “nox,” accessed November 2, 2026, https://dictionary.watkinsx.com/word/nox.

Source: nox on Wiktionary, CC BY-SA 4.0.