Etymologically
Log in

insomnia

History Permalink

Etymology and origin of the Latin word insomnia

Confidence
Established
Formation
Derivation
First attested
c. 250–184 BC Plautus, Mercator More words from the 3rd century BC
Ultimate origin
Latin insomnis
Etymology tree
inherited borrowed derived
Latin somnus
French somme
Italian sonno
Spanish sueño
Latin īnsomnis
Latin īnsomnia
English insomnia
From the same root
Latin īnsomnium ← somnus
Latin sēmisomnus ← somnus
Latin somniculus ← somnus

Pronunciation

  • Classical: [ĩːˈsɔm.ni.a][1]
  • Ecclesiastical: [inˈsɔm.ni.a][1]

Forms

īnsomnia f (genitive īnsomniae); first declension[1]

Etymology

It is formed from Latin insomnis (“sleepless”) + -ia.[2][3][4] The adjective is made of the negative prefix in- and somnus (“sleep”).[5][1]

Earliest recorded meaning

Plautus has it first, in the Mercator, among the troubles that come with love: īnsomnia, aerumna, error, terror et fuga (“sleeplessness, distress, bewilderment, terror and flight”).[2][6]

Semantic evolution

It was a word of the early tragic and comic poets: besides Plautus, Terence, Pacuvius and Caecilius use it.[2][7] Later prose has it in Gellius and Fronto,[2] and the plural meant “sleepless nights”, as in Sallust and Cicero.[7][4] The grammarian Nonius noted that the word was neuter (insomnium) but feminine in Caecilius.[3]

Medieval writers kept the word for wakefulness at night.[8] It passed into Italian as insonnia,[6] and English took it over in the 1620s as insomnie, the form insomnia itself being recorded from 1758.[5]

Timeline

  • c. 250–184 BC – Plautus names sleeplessness among the pains of love.[2][9]
  • 190–159 BC – Terence uses it in the Eunuchus.[2][6]
  • 220–130 BC – Pacuvius uses it in a tragedy.[2][6]
  • 86–34 BC – Sallust uses the plural for sleepless nights.[7]
  • c. 165 AD – Gellius tells of captives tortured to death by keeping them awake.[2][6]
  • 1620s – English borrows it as insomnie;[5] insomnia follows in 1758.[5]

Meanings

Noun

  1. Sleeplessness, want of sleep, insomnia.[2][10][6]
  2. (plural) Sleepless nights.[7][4]

Word family

  • īnsomniōsus

Usage notes

A neuter plural insomnia with the same meaning occurs in Pliny the Elder, Propertius and Valerius Flaccus;[10] the TLL thinks it arose by confusion with insomnium “dream”, whose plural has the same form.[3]

References

  1. ^ a b c d Wiktionary, the free dictionary, https://en.wiktionary.org
  2. ^ a b c d e f g h i 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 Bianchi, Rossella; Lelli, Olga (2014), VOLI: Vocabolario di latino, Florence: Le Monnier
  5. ^ a b c d Harper, Douglas. Online Etymology Dictionary, https://www.etymonline.com
  6. ^ a b c d e f Conte, Gian Biagio; Pianezzola, Emilio; Ranucci, Giuliano (2010), il Latino: Vocabolario della lingua latina, 3rd ed., Florence: Le Monnier
  7. ^ a b c d Georges, Karl Ernst (1913–1918), Ausführliches lateinisch-deutsches Handwörterbuch, 8th ed., ed. Heinrich Georges, Hannover; Leipzig: Hahn
  8. ^ 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
  9. ^ Köbler, Gerhard (2010), Lateinisches Abkunfts- und Wirkungswörterbuch für Altertum und Mittelalter, online ed., koeblergerhard.de
  10. ^ a b Lewis, Charlton T.; Short, Charles (1879), A Latin Dictionary, Oxford: Clarendon Press
Cite this entry

“Insomnia.” Etymologically, 7 Nov. 2026, etymologically.com/la/insomnia. Accessed 8 Nov. 2026.

Last edited on . ·