Lethean

[lee-thee] /ˈli θi/

noun
1.
Classical Mythology. a river in Hades whose water caused forgetfulness of the past in those who drank of it.
2.
(usually lowercase) forgetfulness; oblivion.
/ˈliːθɪ/
noun
1.
(Greek myth) a river in Hades that caused forgetfulness in those who drank its waters
2.
forgetfulness

river of Hades (whose water when drunk caused forgetfulness of the past), from Greek lethe, literally “forgetfulness, oblivion,” related to lethargos “forgetful,” lathre “secretly, by stealth,” lathrios “stealthy,” lanthanein “to be hidden.” Cognate with Latin latere “to be hidden” (see latent). Related: Lethean.
Lethe [(lee-thee)]

In classical mythology, a river flowing through Hades. The souls of the dead were forced to drink of its waters, which made them forget what they had done, said, and suffered when they were alive.

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