Etymologically
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insidiosus

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Pronunciation

  • Classical: [ĩː.sɪ.diˈoː.sʊs][1]
  • Ecclesiastical: [in.si.diˈɔː.s̬us][1]

Forms

īnsidiōsus (feminine īnsidiōsa, neuter īnsidiōsum, comparative īnsidiōsior, superlative īnsidiōsissimus); first/second-declension adjective[1]

Etymology

It is from Latin īnsidiae (“ambush, plot”) + -ōsus.[2][3][1] īnsidiae is from īnsideō (“to sit in, occupy”), from in and sedeō (“to sit”),[1][4] which de Vaan traces to Proto-Italic *sed-ē- and Proto-Indo-European *sed-eh₁- (“to be seated”).[5]

Earliest recorded meaning

Köbler dates it from Cicero,[6] who in the Pro Milone speaks of a man killed in a place full of ambushes and robbers.[2]

Semantic evolution

Of places it means full of ambushes or hidden dangers, as Pliny the Elder's island dangerous to ships; of other things hazardous, as Ovid's treacherous cups of Circe.[2][7] Of people and conduct it is treacherous or deceitful, as Cicero asks who was ever harsher, more treacherous or more cruel.[2][7] Of conditions it means proceeding stealthily, insidious: Publilius Syrus says the greater a thing is, the more treacherous.[2] Church Latin glosses it cunning, artful, deceitful, dangerous.[8] English insidious (1540s) comes from French or directly from Latin.[4]

Timeline

  • 81–43 BC – Cicero of places full of ambushes and of treacherous people.[2][6]
  • 43 BC–18 AD – Ovid of treacherous cups.[2][6]
  • 23/24–79 AD – Pliny the Elder of an island dangerous to ships.[7][6]
  • 1540s – English insidious is formed from it.[4]

Meanings

Adjective

  1. Of places, full of ambushes or hidden dangers; of things, hazardous.[2][7][1]
  2. Of persons and conduct, treacherous, deceitful, cunning.[2][7][1]
  3. Of conditions, proceeding stealthily, insidious.[2][1]

Word family

  • īnsidiōsē

References

  1. ^ a b c d e f g h Wiktionary, the free dictionary, https://en.wiktionary.org
  2. ^ a b c d e f g h i j Glare, P. G. W., ed. (2012), Oxford Latin Dictionary, 2nd ed., Oxford: Oxford University Press
  3. ^ Thesaurus linguae Latinae (1900–), Leipzig: Teubner; Berlin: De Gruyter; open-access ed., Munich: Bayerische Akademie der Wissenschaften
  4. ^ a b c Harper, Douglas. Online Etymology Dictionary, https://www.etymonline.com
  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 c d Köbler, Gerhard (2010), Lateinisches Abkunfts- und Wirkungswörterbuch für Altertum und Mittelalter, online ed., koeblergerhard.de
  7. ^ a b c d e Lewis, Charlton T.; Short, Charles (1879), A Latin Dictionary, Oxford: Clarendon Press
  8. ^ Stelten, Leo F. (1995), Dictionary of Ecclesiastical Latin, Peabody, Mass.: Hendrickson