octavus

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]

Related words

• octō
• English octave

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