Etymologically
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οἶδα

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Pronunciation

  • 5th-century BC Attic: /ôi̯.da/[1]
  • 4th-century AD Koine: /ˈy.ða/[1]
  • 10th-century Byzantine: /ˈy.ða/[1]

Forms

οἶδᾰ (oîda), a perfect with present meaning; 2nd singular οἶσθα (also οἶσθας, Ionic οἶδας), 1st plural ἴσμεν (epic and Ionic ἴδμεν), 3rd plural ἴσᾱσι; imperative ἴσθι; subjunctive εἰδῶ; infinitive εἰδέναι (epic ἴδμεναι); participle εἰδώς, εἰδυῖα; pluperfect ᾔδη; future εἴσομαι.[2][3][4]

Etymology

It is inherited from Proto-Indo-European *wóyde (“has seen, knows”), an old perfect of *weyd- (“to see; to know”): “I have seen” and so “I know”.[1][3][5] It matches Sanskrit वेद (véda, “I know”) exactly, and the Gothic perfect with the same sense.[3][4] Other cognates are Latin vīdī (“I saw”), Old Armenian գիտեմ (gitem, “I know”), a present made from the perfect, and Proto-Slavic *věděti (“to know”).[3][1] Germanic gives English wit.[1] The imperative ἴσθι (ísthi) and the participle εἰδώς (eidṓs) have exact Sanskrit and Gothic counterparts.[3][4]

The aorist εἶδον (eîdon, “I saw”) (infinitive ἰδεῖν (ideîn)) and εἴδομαι (eídomai, “to seem”) are other forms of the same root.[1][3] The o-grade of the singular and the zero grade of the plural are old.[4] The Attic plural with -σ- is probably modelled on the second person.[4]

Earliest recorded meaning

It is common from Homer on: “For I know this well in my mind and my heart” (εὖ γὰρ ἐγὼ τόδε οἶδα κατὰ φρένα καὶ κατὰ θυμόν, Iliad 4.163).[6][2]

Semantic evolution

From Homer on it takes a participle (“to know that one is ...”), a clause, or an indirect question, and with an infinitive means “to know how to”.[2][1] It is used of facts known from report or observation, of things known by divine revelation such as one's fate, of knowing of a person or place, and of knowing someone's character from experience.[2] Chantraine distinguishes it from ἐπίσταμαι (epístamai, “to know how, understand”), with which it partly overlaps.[4] The doubting phrase “I don't know whether ...” goes back to the Iliad.[2]

In Koine and the New Testament the regular forms οἴδαμεν, οἴδατε and οἴδασιν spread, though οἴδασιν is found as early as Herodotus.[7]

Modern Greek Οίδα (ída) survives only as a learned word, mainly in fixed phrases: “who knows”, “the Lord knows”, and “one thing I know, that I know nothing”.[8]

Timeline

  • Homer – The Iliad and the Odyssey use it for knowing facts, persons and skills.[2][9]
  • 5th century BC – Herodotus already has the regular plural οἴδασιν.[7][10]
  • 5th–4th century BC – Plato uses “I don't know how ...”.[2][10]
  • New Testament – The forms οἴδαμεν, οἴδατε, οἴδασιν are usual.[7]
  • Modern Greek – οίδα survives in learned phrases such as “who knows”.[8]

Meanings

Verb

  1. To know, to have seen or been made aware of something; with a participle, a clause or an indirect question, to know that or what.[2][1]
  2. To be aware of an event or a piece of information, from report or one's own observation.[2]
  3. To know by intuition or revelation (a fate, the future, the truth).[2]
  4. To know of a person, god, place or road as existing.[2]
  5. To be acquainted with, to know from experience; with a genitive, to be skilled in.[2][1]
  6. With an infinitive, to know how to do something.[1][2]

Word family

  • πρόοιδα (próoida)
  • σύνοιδα (súnoida)
  • εἴδομαι (eídomai)
  • εἶδον (eîdon)

References

  1. ^ a b c d e f g h i j k Wiktionary, the free dictionary, https://en.wiktionary.org
  2. ^ a b c d e f g h i j k l m Diggle, James, et al., eds. (2021), The Cambridge Greek Lexicon, Cambridge: Cambridge University Press
  3. ^ a b c d e f Beekes, Robert S. P. (2010), Etymological Dictionary of Greek, with the assistance of Lucien van Beek, Leiden Indo-European Etymological Dictionary Series 10, Leiden; Boston: Brill
  4. ^ a b c d e f Chantraine, Pierre (2009), Dictionnaire étymologique de la langue grecque: histoire des mots, new ed. with a supplement (Chroniques d'étymologie grecque 1–10), Paris: Klincksieck
  5. ^ Rix, Helmut, et al. (2001), Lexikon der indogermanischen Verben, 2nd ed., Wiesbaden: Reichert
  6. ^ Babiniotis, Georgios (2010), Ετυμολογικό λεξικό της νέας ελληνικής γλώσσας [Etymological Dictionary of Modern Greek], Athens: Κέντρο Λεξικολογίας
  7. ^ a b c Bauer, Walter; Danker, Frederick W., et al. (2000), A Greek-English Lexicon of the New Testament and Other Early Christian Literature, 3rd ed., Chicago: University of Chicago Press
  8. ^ a b Ινστιτούτο Νεοελληνικών Σπουδών (Ίδρυμα Μανόλη Τριανταφυλλίδη) (1998), Λεξικό της κοινής νεοελληνικής, Thessaloniki: Aristotle University of Thessaloniki
  9. ^ Keersmaekers, Alek (2021–2025), GLAUx: The Greek Language Automated corpus, https://github.com/alekkeersmaekers/glaux
  10. ^ a b Rodríguez Adrados, Francisco, et al., eds. (1980–), Diccionario Griego-Español, Madrid: CSIC, http://dge.cchs.csic.es/xdge