Lethe in Greek and Roman Biography and Mythology
（Λήθη), the personification of oblivion, is called by Hesiod
(Hes. Th. 227) a daughter of Eris. A river in the lower world
likewise bore the name of Lethe. [HADES.] - A Dictionary of
Greek and Roman biography and mythology, William Smith, Ed.
Lethe in Wikipedia
In Greek mythology, Lethe (Λήθη; Classical Greek /ˈlɛːtʰɛː/,
modern Greek: /ˈliθi/) was one of the five rivers of Hades.
Also known as the Ameles potamos (river of unmindfulness), the
Lethe flowed around the cave of Hypnos and through the
Underworld, where all those who drank from it experienced
complete forgetfulness. Lethe was also the name of the Greek
spirit of forgetfulness and oblivion, with whom the river was
In Classical Greek, the word Lethe literally means "oblivion",
"forgetfulness," or "concealment". It is related to the Greek
word for "truth", aletheia (αλήθεια), meaning "un-
forgetfulness" or "un-concealment"...