Etymologically
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opacus

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Pronunciation

  • IPA (Classical): [ɔˈpaː.kʊs][1]
  • IPA (Ecclesiastical): [oˈpaː.kus][1]

Forms

opācus (feminine opāca, neuter opācum); first/second-declension adjective[1]

Etymology

Its origin is unknown.[2][1][3] It has long been compared with Sanskrit अपाक (ápāka-, “turned away”) and Russian опако (opako, “backwards”), but these go back to *h₂epo-h₃kʷ- and would give Latin *apōcus.[2][4] De Vaan mentions a possible *op-wāko- “towards the empty side”, from the root of vacuus and vānus, as only a theoretical possibility.[2] It is the opposite of aprīcus “sunny”.[1]

Earliest recorded meaning

De Vaan dates it from Lucretius, Köbler from Cicero, who strolls on a green and shady river bank among tall poplars.[2][5][3] Köbler dates Lucretius 96–55 BC and Cicero 81–43 BC.[5]

Semantic evolution

It meant sheltered from the sun, shady, as Cicero's bank and Virgil's cool shade, and giving dense shade, as Virgil's elm in the underworld.[3][6] Of night and darkness it meant dark and dim, as Lucretius' sun shining through a dark storm.[3]

It survives in Spanish obago and Catalan obac “shady slope”, and English opaque was taken from it in the early 15th century, “dark, shaded”, with its spelling later changed after French.[1][7]

Timeline

  • 96–55 BC – Lucretius speaks of a dark storm.[3][5]
  • 81–43 BC – Cicero speaks of a shady river bank.[3][5]
  • 70–19 BC – Virgil speaks of the cool shade.[6][5]
  • early 15th century – English opaque is recorded.[7]

Meanings

Adjective

  1. Sheltered from the sun, shady.[3]
  2. Giving dense shade.[3]
  3. Dark, dim.[3]

Word family

  • opācitās
  • opācō
  • peropacus

References

  1. ^ a b c d e f Wiktionary, the free dictionary, https://en.wiktionary.org
  2. ^ a b c d 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 Glare, P. G. W., ed. (2012), Oxford Latin Dictionary, 2nd ed., Oxford: Oxford University Press
  4. ^ Thesaurus linguae Latinae (1900–), Leipzig: Teubner; Berlin: De Gruyter; open-access ed., Munich: Bayerische Akademie der Wissenschaften
  5. ^ a b c d e Köbler, Gerhard (2010), Lateinisches Abkunfts- und Wirkungswörterbuch für Altertum und Mittelalter, online ed., koeblergerhard.de
  6. ^ a b Gaffiot, Félix (2016), Dictionnaire latin-français, new ed. by Gérard Gréco et al. (Gaffiot 2016), online ed.
  7. ^ a b Harper, Douglas. Online Etymology Dictionary, https://www.etymonline.com