infallibilis

Forms

īnfallibilis (neuter īnfallibile); third-declension two-termination adjective^[1][2]

Etymology

It is formed from Latin in- + fallibilis.^[1][3] The DMLBS labels it a Medieval Latin word.^[4]

Earliest recorded meaning

Gaffiot cites it, in the sense “infallible”, from Bede,^[2] who wrote in the first third of the 8th century.^[1]

Semantic evolution

Medieval writers used it actively, of what does not deceive: sure, reliable signs, documents, reckonings and rules.^[5][4] Lambert of Ardres praises the careful and infallible reckoning of the Hebrews, and John of Garland a principle of music that no one can contradict.^[5] Used passively, it meant that cannot be deceived, free from error, and it was said of God's wisdom and of judgments.^[5][4] Gerald of Wales has it in the sense “unfailing”.^[4] It is an Ecclesiastical Latin word.^[6]

English infallible comes from the Medieval Latin word (early 15th century); its use of popes dates from 1870.^[3]

Timeline

• 1st third of the 8th century – Bede uses it, as Gaffiot records.^[2][1]
• 1258 – The Close Rolls speak of “many infallible proofs”.^[4]
• 1st half of the 14th century – Ockham uses it.^[4][1]
• early 15th century – English borrows it as infallible.^[3]
• 1870 – English infallible is first used of popes.^[3]

Meanings

Adjective

1. (Medieval Latin) That does not deceive or mislead; sure, reliable.^[5][4]
2. (Medieval Latin) That cannot err or be deceived, infallible.^[5][4][6]
3. (Medieval Latin) Unfailing.^[4]

Related words

• fallō

References

1. ^ a b c d e Köbler, Gerhard (2010), Lateinisches Abkunfts- und Wirkungswörterbuch für Altertum und Mittelalter, online ed., koeblergerhard.de
2. ^ a b c Gaffiot, Félix (2016), Dictionnaire latin-français, new ed. by Gérard Gréco et al. (Gaffiot 2016), online ed.
3. ^ a b c d Harper, Douglas. Online Etymology Dictionary, https://www.etymonline.com
4. ^ a b c d e f g h i 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
5. ^ a b c d e Mittellateinisches Wörterbuch bis zum ausgehenden 13. Jahrhundert (1967–), Munich: C. H. Beck; Bayerische Akademie der Wissenschaften
6. ^ a b Stelten, Leo F. (1995), Dictionary of Ecclesiastical Latin, Peabody, Mass.: Hendrickson