Rhotacization of earlier *diusnus, from diūs (old nominative of diēs) +‎ -nus (suffix forming adjectives). Re-analysed as diū (by day) +‎ -rnus.



diurnus (feminine diurna, neuter diurnum); first/second-declension adjective

  1. of the day
  2. daily


First/second-declension adjective.

Number Singular Plural
Case / Gender Masculine Feminine Neuter Masculine Feminine Neuter
Nominative diurnus diurna diurnum diurnī diurnae diurna
Genitive diurnī diurnae diurnī diurnōrum diurnārum diurnōrum
Dative diurnō diurnō diurnīs
Accusative diurnum diurnam diurnum diurnōs diurnās diurna
Ablative diurnō diurnā diurnō diurnīs
Vocative diurne diurna diurnum diurnī diurnae diurna


Derived termsEdit


diurnus m (genitive diurnī); second declension

  1. (Medieval Latin) day


Second-declension noun.

Case Singular Plural
Nominative diurnus diurnī
Genitive diurnī diurnōrum
Dative diurnō diurnīs
Accusative diurnum diurnōs
Ablative diurnō diurnīs
Vocative diurne diurnī


  • Italo-Dalmatian:
    • Corsican: ghjornu
    • Italian: giorno
    • Neapolitan: juorno
    • Sicilian: jornu
    • Venetian: zorno, giorno
  • Gallo-Romance:
  • Occitano-Romance:
  • Ibero-Romance:
  • Ido: jorno

See also descendants at diurnāta.


  • diurnus in Charlton T. Lewis and Charles Short (1879) A Latin Dictionary, Oxford: Clarendon Press
  • diurnus in Charlton T. Lewis (1891) An Elementary Latin Dictionary, New York: Harper & Brothers
  • diurnus in Charles du Fresne du Cange’s Glossarium Mediæ et Infimæ Latinitatis (augmented edition with additions by D. P. Carpenterius, Adelungius and others, edited by Léopold Favre, 1883–1887)
  • diurnus in Gaffiot, Félix (1934) Dictionnaire illustré Latin-Français, Hachette
  • Carl Meißner; Henry William Auden (1894) Latin Phrase-Book[1], London: Macmillan and Co.
    • travelling day and night: itinera diurna nocturnaque