Etymologically
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duo

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Pronunciation

  • IPA (Classical): [ˈdu.ɔ][1]
  • IPA (Ecclesiastical): [ˈduː.o][1]

Forms

duo (feminine duae, neuter duo); numeral, plural only[1] The accusative masculine is duōs or duo, and inscriptions have a neuter dua, which Quintilian calls a barbarism.[2][3][4] The genitive is duōrum or duum.[2][5]

Etymology

It is inherited from Proto-Italic *duō, inherited from Proto-Indo-European *du-o-h₁ (“two”), an old dual; the final vowel was shortened.[2][1] Cognate with Umbrian dur (“two”), Old Irish dáu (“two”), Sanskrit द्व (dvá, “two”), Ancient Greek δύο (dúo, “two”), Old Church Slavonic дъва (dŭva, “two”) and Old English twā (“two”).[2][1][3]

Earliest recorded meaning

It appears in Very Old Latin and in Naevius.[2] Köbler dates Naevius c. 235–200 BC.[6]

Semantic evolution

It was the number two, and with the article sense “the two, both”.[7][3] It formed duodecim “twelve”, ducentī “two hundred” and duumvirī, a board of two men.[2]

Proto-Romance */ˈdʊ-i/ “two” is continued in all Romance languages.[8] It survives as Italian due, French deux, Portuguese dois and Romanian doi.[1] English dual comes from duālis, and double from duplus.[9]

Timeline

  • c. 235–200 BC – Naevius uses it.[2][6]
  • c. 1300 – English double is recorded, from Old French doble, from duplus.[9]
  • c. 1600 – English dual is recorded, from duālis.[9]

Meanings

Numeral

  1. Two.[3][4]
  2. The two, both.[7][10]

Word family

  • duālis
  • ducentī
  • ducentum
  • duōdecas
  • duodecim
  • duodennis

Usage notes

Isidore says there are two kinds of offering, a gift and a sacrifice.[11]

References

  1. ^ a b c d e f Wiktionary, the free dictionary, https://en.wiktionary.org
  2. ^ a b c d e f g 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 Glare, P. G. W., ed. (2012), Oxford Latin Dictionary, 2nd ed., Oxford: Oxford University Press
  4. ^ a b Lewis, Charlton T.; Short, Charles (1879), A Latin Dictionary, Oxford: Clarendon Press
  5. ^ Gaffiot, Félix (2016), Dictionnaire latin-français, new ed. by Gérard Gréco et al. (Gaffiot 2016), online ed.
  6. ^ a b Köbler, Gerhard (2010), Lateinisches Abkunfts- und Wirkungswörterbuch für Altertum und Mittelalter, online ed., koeblergerhard.de
  7. ^ a b Georges, Karl Ernst (1913–1918), Ausführliches lateinisch-deutsches Handwörterbuch, 8th ed., ed. Heinrich Georges, Hannover; Leipzig: Hahn
  8. ^ Buchi, Éva; Schweickard, Wolfgang, eds. (2008–), Dictionnaire Étymologique Roman (DÉRom), Nancy: ATILF, http://www.atilf.fr/DERom
  9. ^ a b c Harper, Douglas. Online Etymology Dictionary, https://www.etymonline.com
  10. ^ Mittellateinisches Wörterbuch bis zum ausgehenden 13. Jahrhundert (1967–), Munich: C. H. Beck; Bayerische Akademie der Wissenschaften
  11. ^ Isidore of Seville, Etymologiarum sive Originum libri XX, ed. W. M. Lindsay (Oxford, 1911).