Etymologically
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octavus

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Pronunciation

  • Classical: [ɔkˈtaː.wʊs][1]
  • Ecclesiastical: [okˈtaː.vus][1]

Forms

octāvus (feminine octāva, neuter octāvum); first/second-declension numeral[1]

Etymology

It is inherited from Proto-Italic *oktāwo- (“eighth”), inherited from Proto-Indo-European *h3ḱt(e)h3-uó- (“eighth”), from Proto-Indo-European *h3(e)ḱtéh3 (“eight”), the source of octō.[2][1] The ⟨ā⟩ is unexpected for ⟨*ō⟩;[2][3] Schrijver explains it as a loss of rounding before the following ⟨u⟩.[2][3] Cognate with Ancient Greek ὄγδοος (ógdoos, “eighth”), Sanskrit अष्टम (aṣṭamá-, “eighth”) and Old Irish ochtmad (“eighth”).[2]

Earliest recorded meaning

Köbler's first source is Plautus;[4] de Vaan dates it from Cato.[2]

Semantic evolution

It means “eighth”, as Cicero's eighth part and Caesar's eighth legion;[5][3] Martial calls the eighth milestone simply octāvum marmor.[5][3] The feminine octāva is the eighth hour of the day, and an eighth part, in Late Latin a tax of an eighth on produce;[3][5] cum octāvō is “with an eightfold yield”, of corn in Cicero.[3][5] The neuter octāvum means “for the eighth time” in Livy.[5]

In Medieval Latin octāva, the eighth day, gave English octave, first of the eighth day after a church feast.[6]

Timeline

  • c. 250–184 BC – Plautus.[4]
  • 234–149 BC – Cato.[2][4]
  • 81–43 BC – Cicero of an eightfold yield.[3][4]
  • c. 50 BC – Caesar of the eighth legion.[5][4]
  • c. 1300 – English octave comes from Medieval Latin octāva.[6]

Meanings

Adjective

  1. Eighth.[3][5][1][7]
  2. octāva, the eighth hour; an eighth part; a tax of an eighth.[3][5]
  3. cum octāvō, with an eightfold yield.[3]
  4. octāvum, for the eighth time.[5]

References

  1. ^ a b c d e Wiktionary, the free dictionary, https://en.wiktionary.org
  2. ^ a b c d e f de Vaan, Michiel (2008), Etymological Dictionary of Latin and the other Italic Languages, Leiden Indo-European Etymological Dictionary Series 7, Leiden; Boston: Brill
  3. ^ a b c d e f g h i j Glare, P. G. W., ed. (2012), Oxford Latin Dictionary, 2nd ed., Oxford: Oxford University Press
  4. ^ a b c d e Köbler, Gerhard (2010), Lateinisches Abkunfts- und Wirkungswörterbuch für Altertum und Mittelalter, online ed., koeblergerhard.de
  5. ^ a b c d e f g h i Lewis, Charlton T.; Short, Charles (1879), A Latin Dictionary, Oxford: Clarendon Press
  6. ^ a b Harper, Douglas. Online Etymology Dictionary, https://www.etymonline.com
  7. ^ Stelten, Leo F. (1995), Dictionary of Ecclesiastical Latin, Peabody, Mass.: Hendrickson