Etymologically
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perfidiosus

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Pronunciation

  • Classical: [pɛr.fɪ.diˈoː.sʊs][1]
  • Ecclesiastical: [per.fi.diˈɔː.s̬us][1]

Forms

perfidiōsus (feminine perfidiōsa, neuter perfidiōsum, comparative perfidiōsior); first/second-declension adjective[1]

Etymology

It is from Latin perfidia (“faithlessness, treachery”) + -ōsus (“full of”).[2][1][3] perfidia is from perfidus (“faithless”), made from per- and fidēs1 (“trust”).[1] De Vaan traces that noun to Proto-Indo-European *bhidh-eh1- (“faith”), beside the verb fīdō (“to trust”), from Proto-Indo-European *bheidh-e/o- (“to trust”).[4]

Earliest recorded meaning

The TLL records it from Plautus on,[3] who writes perfidiosus est Amor, “Love is treacherous”.[5]

Semantic evolution

It means faithless, treacherous, false, of persons and of things.[2][6] The TLL finds it in Plautus and the Rhetorica ad Herennium but rarely elsewhere except in Cicero, who uses it about ten times;[3] Cicero calls one man omnium perfidiosissimus, “the most treacherous of all”, and says that it is perfidiosum to break one's word.[7][6] Tacitus has perfidiosus et subdolus animo, “treacherous and crafty in mind”.[6][5] In Ecclesiastical Latin it keeps the sense faithless, treacherous,[8] and medieval glossaries in Britain explain it as one who always breaks faith.[9] English borrowed it as perfidious in the 1590s.[10]

Timeline

  • c. 250–184 BC – Plautus writes perfidiosus est Amor.[3][5][11]
  • 81–43 BC – Cicero uses it about ten times.[3][11]
  • 98–115 AD – Tacitus has perfidiosus et subdolus animo.[6][11]
  • 1590s – English borrows it as perfidious.[10]

Meanings

Adjective

  1. Faithless, treacherous, perfidious, false.[2][6][8]

References

  1. ^ a b c d e Wiktionary, the free dictionary, https://en.wiktionary.org
  2. ^ a b c Glare, P. G. W., ed. (2012), Oxford Latin Dictionary, 2nd ed., Oxford: Oxford University Press
  3. ^ a b c d e Thesaurus linguae Latinae (1900–), Leipzig: Teubner; Berlin: De Gruyter; open-access ed., Munich: Bayerische Akademie der Wissenschaften
  4. ^ de Vaan, Michiel (2008), Etymological Dictionary of Latin and the other Italic Languages, Leiden Indo-European Etymological Dictionary Series 7, Leiden; Boston: Brill
  5. ^ a b c Conte, Gian Biagio; Pianezzola, Emilio; Ranucci, Giuliano (2010), il Latino: Vocabolario della lingua latina, 3rd ed., Florence: Le Monnier
  6. ^ a b c d e Lewis, Charlton T.; Short, Charles (1879), A Latin Dictionary, Oxford: Clarendon Press
  7. ^ Georges, Karl Ernst (1913–1918), Ausführliches lateinisch-deutsches Handwörterbuch, 8th ed., ed. Heinrich Georges, Hannover; Leipzig: Hahn
  8. ^ a b Stelten, Leo F. (1995), Dictionary of Ecclesiastical Latin, Peabody, Mass.: Hendrickson
  9. ^ 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
  10. ^ a b Harper, Douglas. Online Etymology Dictionary, https://www.etymonline.com
  11. ^ a b c Köbler, Gerhard (2010), Lateinisches Abkunfts- und Wirkungswörterbuch für Altertum und Mittelalter, online ed., koeblergerhard.de