LATIN DICTIONARYLexicon Latīnum
adjectivefirst/second-declension adjective

Lēthaeus

Lēthaeus (feminine Lēthaea, neuter Lēthaeum)
Classical[ɫeːˈtʰae̯.ʊs]Ecclesiastical[leˈtɛː.us]

Meaning

  1. adjectiveof or pertaining to Lethe, Lethean
  2. adjectiveof the underworld, of the infernal regions
    Lethaei dii.Gods of the underworld.
    Lethaea vincula abrumpere alicui.To bring one from the Lower World back to life.
  3. adjectivecausing forgetfulness or sleepiness

Declension

singular
formmasculinefeminineneuter
nominativeLēthaeusLēthaeaLēthaeum
genitiveLēthaeīLēthaeaeLēthaeī
dativeLēthaeōLēthaeaeLēthaeō
accusativeLēthaeumLēthaeamLēthaeum
ablativeLēthaeōLēthaeāLēthaeō
vocativeLēthaeeLēthaeaLēthaeum
plural
formmasculinefeminineneuter
nominativeLēthaeīLēthaeaeLēthaea
genitiveLēthaeōrumLēthaeārumLēthaeōrum
dativeLēthaeīsLēthaeīsLēthaeīs
accusativeLēthaeōsLēthaeāsLēthaea
ablativeLēthaeīsLēthaeīsLēthaeīs
vocativeLēthaeīLēthaeaeLēthaea

Lēthaeus, a, um, v. Lethe, II.

Origins

Borrowed from Ancient Greek λήθαιος (lḗthaios), ληθαῖος (lēthaîos).

In the Academy Smith's classical dictionaries

GeographyLethaeusLethaeus (Ληθαῖος), a small river of Caria, which has its sources in Mount Pactyes, and after a short course from north to south discharges itself int…

Quick answers

What does Lēthaeus mean in Latin?
Lēthaeus, a adjective, means “of or pertaining to Lethe, Lethean; of the underworld, of the infernal regions; causing forgetfulness or sleepiness”.
How do you pronounce Lēthaeus?
In classical Latin, [ɫeːˈtʰae̯.ʊs]; in ecclesiastical (church) Latin, [leˈtɛː.us].