opacus

Latin

Etymology

Unknown. Possibly related to Ancient Greek παχύς (pakhús, “thick”) or from Proto-Indo-European *apó.

Pronunciation

• (Classical) IPA^(key): /oˈpaː.kus/, [ɔˈpäːkʊs̠]
• (modern Italianate Ecclesiastical) IPA^(key): /oˈpa.kus/, [oˈpäːkus]

Adjective

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

1. shaded, darkened; in the shade
2. shady, dark; casting shade
3. obscure
4. opaque

   Synonym: obscūrus

   Antonyms: lūcidus, clārus

Declension

First/second-declension adjective.

Number	Singular				Plural
Case / Gender	Masculine	Feminine	Neuter		Masculine	Feminine	Neuter
Nominative	opācus	opāca	opācum		opācī	opācae	opāca
Genitive	opācī	opācae	opācī		opācōrum	opācārum	opācōrum
Dative	opācō		opācō		opācīs
Accusative	opācum	opācam	opācum		opācōs	opācās	opāca
Ablative	opācō	opācā	opācō		opācīs
Vocative	opāce	opāca	opācum		opācī	opācae	opāca

Derived terms

• opācitās
• opācō

Descendants

• Padanian:
  • Ligurian: lǜvegu
  • Lombard: vag
  • Piedmontese: uvac, uvai, vai
  • Romagnol: bègh
  • Romansch: vac
• Southern Gallo-Romance:
  • Aragonese: paco, bago, ubago
  • Catalan: obac
  • Occitan: ubac

    ⇒ Gascon: paquís

    • → English: ubac
• ⇒ Vulgar Latin: *opacīnus
  • Aragonese: pacín, pacino
• ⇒ Vulgar Latin: *opacivus
  • Italian: bacio
• Borrowings:
  • → Catalan: opac
  • → English: opaque
  • → French: opaque
    • → Romanian: opac
    • → Turkish: opak
  • → Galician: opaco
  • → Italian: opaco
  • → Piedmontese: opach
  • → Portuguese: opaco
  • → Spanish: opaco

References

• “opacus”, in Charlton T. Lewis and Charles Short (1879) A Latin Dictionary, Oxford: Clarendon Press
• “opacus”, in Charlton T. Lewis (1891) An Elementary Latin Dictionary, New York: Harper & Brothers
• opacus in Gaffiot, Félix (1934) Dictionnaire illustré latin-français, Hachette.

Further reading

• “opacus”, in Charlton T. Lewis and Charles Short (1879) A Latin Dictionary, Oxford: Clarendon Press