Etymologically

Etymology and origin of the Latin word eiuro

Confidence
Established
Formation
Derivation
First attested
c. 250–184 BC, Plautus
Ultimate origin
Proto-Indo-European (*h₂oi-u)
Etymology tree
inherited borrowed derived
Latin ius
Latin iuro
French jurer
Latin eiuro
Latin coniuro
Latin coniuratio
Latin iustitium

Pronunciation

  • Classical: [eːˈjuː.roː][1]
  • Ecclesiastical: [eˈjuː.ro][1]

Forms

ēiūrō (present infinitive ēiūrāre, perfect active ēiūrāvī, supine ēiūrātum); first conjugation[1] The form ēierō is the classical one, and Plautus has exiūr-.[2][3]

Etymology

It is from Latin ex- + iūrō (“to swear”).[2][4][1] The TLL leaves open whether the variant ⟨ēierō⟩ is the same word or related to it by vowel alternation, as with dēierō and pēierō.[4] De Vaan derives iūrō from iūs2 (“law; oath”), from Proto-Italic *jowos (“oath, law”) and Proto-Indo-European *h₂oi-u (“vital force, eternity”).[5]

Earliest recorded meaning

Plautus has it first: a fragment quoted by Paulus' Festus has swearing oneself unfit for military service, and the Amphitruo a form ⟨exiūr-⟩.[2][3]

Semantic evolution

Lewis & Short call it a technical term of law, politics and commerce.[3] In law it is to reject a court or judge on oath as unfair, as in a saying of Scipio quoted by Cicero and in the Verrines;[2][3] bonam cōpiam ēiūrāre is to swear that one is insolvent.[2][3] In politics it is to resign an office, swearing that one has kept the laws, often in Tacitus.[2][3] More widely it is to disown one's country or children, as Tacitus and Seneca have, and Statius uses it of a tame lion that forswears its loyalty.[3][2] Lewis & Short note that ēierō is the classical form and ēiūrō mostly post-Augustan.[3] Stelten gives “deny, refuse, abandon”.[6]

Timeline

  • c. 250–184 BC – Plautus, of swearing oneself unfit for service.[2][3][7]
  • 81–43 BC – Cicero, of rejecting a judge on oath.[2][3][7]
  • 98–115 AD – Tacitus, of resigning an office.[2][3][7]

Meanings

Verb

  1. To swear that one cannot perform a service;[2][3] bonam cōpiam ēiūrāre, to swear oneself insolvent.[2][3]
  2. (law) To reject (a judge or court) on oath as partial.[2][3][1]
  3. To resign an office on oath.[2][3][1]
  4. To disown, abjure, forswear, renounce.[2][3][1][6]
  5. To swear solemnly that.[2]

Word family

  • ēiurātiō

References

  1. ^ a b c d e f g Wiktionary, the free dictionary, https://en.wiktionary.org
  2. ^ a b c d e f g h i j k l m n o p Glare, P. G. W., ed. (2012), Oxford Latin Dictionary, 2nd ed., Oxford: Oxford University Press
  3. ^ a b c d e f g h i j k l m n o p Lewis, Charlton T.; Short, Charles (1879), A Latin Dictionary, Oxford: Clarendon Press
  4. ^ a b Thesaurus linguae Latinae (1900–), Leipzig: Teubner; Berlin: De Gruyter; open-access ed., Munich: Bayerische Akademie der Wissenschaften
  5. ^ de Vaan, Michiel (2008), Etymological Dictionary of Latin and the other Italic Languages, Leiden Indo-European Etymological Dictionary Series 7, Leiden; Boston: Brill
  6. ^ a b Stelten, Leo F. (1995), Dictionary of Ecclesiastical Latin, Peabody, Mass.: Hendrickson
  7. ^ a b c Köbler, Gerhard (2010), Lateinisches Abkunfts- und Wirkungswörterbuch für Altertum und Mittelalter, online ed., koeblergerhard.de
Cite this entry

“Eiuro.” Etymologically, 20 Oct. 2026, etymologically.com/la/eiuro. Accessed 20 Oct. 2026.

Last edited on . ·