кануть в реку забвения

• КАНУТЬ В ЛЕТУ (в РЕКУ ЗАБВЕНИЯ obs) lit

[VP; subj: abstr or human; fixed WO]

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⇒ to disappear completely, be forgotten forever:

- X канул в Лету{{}}≈ X was swallowed up by Lethe (in the river of oblivion);

- X sank into oblivion.

     ♦ "Так, понимаете, и слухи о капитане Копейкине канули в реку забвения, в какую-нибудь эдакую Лету, как называют поэты" (Гоголь 3). "It was thus, you understand, that the rumours about Captain Kopeikin were swallowed up in the river of oblivion, in this-er-Lethe, as the poets call it" (3a).

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← From Lethe ("Лета"), the name of a river in Hades. In classical mythology, those who drank the water of Lethe-also called "the river of oblivion" ("река забвения") - forgot the past.