aperio

From Proto-Italic *apwerjō, from Proto-Indo-European *h₂epó (“off, from”) (whence ab) + *h₂wer- (“to cover, shut”) +‎ *-ye-.^[1] Cognate with Sanskrit अपिवृणोति (apivṛṇoti, “to close, cover”), Oscan veru (“door”, pl.), Ancient Greek ἀείρω (aeírō, “to lift, raise”), Lithuanian atvérti (“to open”), Proto-Slavic *ot(ъ)verti (“to open”), and Old Armenian գեր (ger, “above, hyper-”). Related to operiō (“to cover”).

• (Classical Latin) IPA^(key): /aˈpe.ri.oː/, [äˈpɛrioː]
• (modern Italianate Ecclesiastical) IPA^(key): /aˈpe.ri.o/, [äˈpɛːrio]

aperiō (present infinitive aperīre, perfect active aperuī, supine apertum); fourth conjugation

1. (literal) to uncover, make or lay bare, reveal, clear

   Synonym: adaperiō

   Antonyms: vēlō, dissimulō, occultō, indūcō, operiō, obnūbō, occulō, condō, recondō, verrō, obruō, adoperiō, nūbō, tegō, abdō, abscondō, cooperiō, premō, opprimō, mergō

   • 8 CE, Ovid, Fasti 1.681:

     cum serimus, caelum ventīs aperīte serēnīs

     When we are sowing, you (pl.) clear* the sky with fair winds.
     *(In this quotation, the imperative plural aperīte is invoking the goddesses Terra and Ceres.)

2. (figurative) to make visible, discover, show, reveal, lay open
   • 405 CE, Jerome, Vulgate Proverbs.13.16:

     Astūtus omnia agit cum cōnsiliō: quī autem fatuus est aperit stultitiam.

     The prudent man doth all things with counsel: but he that is a fool, layeth open his folly.
     (Douay-Rheims trans., Challoner rev.: 1752 CE)

3. (figurative)
   1. to unclose, open, break open

      Synonyms: adaperiō, patefaciō

      Antonyms: interclūdō, claudō, inclūdō, arceō, obserō, operiō

      1. (figurative) to open, set up, establish, begin
   2. to open an entrance to, render accessible
   3. (transferred sense, to mental objects) to disclose something unknown, to unveil, reveal, make known, unfold, prove, demonstrate; (in general) to explain, recount

This entry needs quotations to illustrate usage. If you come across any interesting, durably archived quotes then please add them!

• “aperio”, in Charlton T. Lewis and Charles Short (1879) A Latin Dictionary, Oxford: Clarendon Press
• “aperio”, in Charlton T. Lewis (1891) An Elementary Latin Dictionary, New York: Harper & Brothers
• aperio in Gaffiot, Félix (1934) Dictionnaire illustré latin-français, Hachette.
• Carl Meißner, Henry William Auden (1894) Latin Phrase-Book‎^[1], London: Macmillan and Co.
  • to open a route: viam patefacere, aperire
    
  • to uncover one's head: caput aperire (opp. operire)
    
  • to freely express one's opinions: sententiam suam aperire
    
  • to make an obscure notion clear by means of definition: involutae rei notitiam definiendo aperire (Or. 33. 116)
    
  • to explain one's sentiments: sententias (verbis) explicare, aperire
    
  • to open a letter: epistulam solvere, aperire, resignare (of Romans also linum incīdere)
    
  • to open, shut the door: ostium, fores aperire, claudere