ληθαῖος
From LSJ
καὶ οὐκ ἐκδικᾶταί σου ἡ χείρ, καὶ οὐ μηνιεῖς τοῖς υἱοῖς τοῦ λαοῦ σου καὶ ἀγαπήσεις τὸν πλησίον σου ὡς σεαυτόν· ἐγώ εἰμι κύριος. Τὸν νόμον μου φυλάξεσθε → Let your hand not seek vengeance; do not show wrath toward the children of your people; love your neighbor as yourself. I am the Lord! Keep my Torah! (Leviticus 19:18f. LXX)
German (Pape)
[Seite 38] zur Vergessenheit gehörig, vergeßlich oder vergessen lassend, ὅτε οἱ ληθαῖον ἐπἲ πτερὸν ὕπνος ἐρείσει, den das Uebel vergessen lassenden Fittig des Schlafes, Csilim. Del. 233; vgl. Nonn. D. 7, 141. – Häufiger von Λήθη, s. nom. pr.
Russian (Dvoretsky)
ληθαῖος: забывчивый Sext.