Etymologically
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irrationabilis

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Pronunciation

  • Classical: [ɪr.ra.ti.oːˈnaː.bɪ.lɪs][1]
  • Ecclesiastical: [ir.rat.t͡si.oˈnaː.bi.lis][1]

Forms

irratiōnābilis (neuter irratiōnābile); third-declension two-termination adjective[1] Also spelled inrationabilis.[2][3]

Etymology

It is from Latin in- + ratiōnābilis (“reasonable”), with the negative prefix.[2][3][4]

Earliest recorded meaning

The OLD's earliest citations are from the declamations transmitted under Quintilian's name, which speak of “unreasoning impulses of the mind”;[2] Apuleius' work on Plato also has it.[2] Lewis and Short call it post-classical and note that it is not in Quintilian himself.[5]

Semantic evolution

It meant “unreasoning, irrational”: Ammianus Marcellinus has it of a movement, and Lactantius uses the neuter plural as a noun for unreasoning creatures.[5][6] Georges notes that in good classical writers such as Celsus the manuscripts' irrationabilis should be read as irrationalis.[6] In translations from Greek it usually stands for ἄλογος (álogos).[3]

In medieval Latin it described people and peoples without reason, irrational animals (Bede contrasts man with the unreasoning beasts) and things,[7] and also meant “unreasonable” and “groundless, unjustified”.[8]

Timeline

  • c. 125–175 AD – Apuleius uses it in his work on Plato.[2][4]
  • c. 250–317 AD – Lactantius uses irrationabilia for unreasoning creatures.[5][4]
  • c. 390 AD – Ammianus Marcellinus has it of a movement.[5][4]

Meanings

Adjective

  1. Unreasoning, irrational.[2][5]
  2. As a neuter plural noun, irratiōnābilia: unreasoning creatures, brutes.[5][6]
  3. (Medieval Latin) Unreasonable.[8]
  4. (Medieval Latin) Groundless, unjustified.[8]

Word family

  • irrationabilitas

References

  1. ^ a b c Wiktionary, the free dictionary, https://en.wiktionary.org
  2. ^ a b c d e f Glare, P. G. W., ed. (2012), Oxford Latin Dictionary, 2nd ed., Oxford: Oxford University Press
  3. ^ a b c Thesaurus linguae Latinae (1900–), Leipzig: Teubner; Berlin: De Gruyter; open-access ed., Munich: Bayerische Akademie der Wissenschaften
  4. ^ a b c d Köbler, Gerhard (2010), Lateinisches Abkunfts- und Wirkungswörterbuch für Altertum und Mittelalter, online ed., koeblergerhard.de
  5. ^ a b c d e f Lewis, Charlton T.; Short, Charles (1879), A Latin Dictionary, Oxford: Clarendon Press
  6. ^ a b c Georges, Karl Ernst (1913–1918), Ausführliches lateinisch-deutsches Handwörterbuch, 8th ed., ed. Heinrich Georges, Hannover; Leipzig: Hahn
  7. ^ Latham, R. E., D. R. Howlett, R. K. Ashdowne, et al. (1975–2013), Dictionary of Medieval Latin from British Sources, London: British Academy / Oxford University Press
  8. ^ a b c Niermeyer, J. F. (1976), Mediae Latinitatis Lexicon Minus, Leiden: Brill