Something that is a certainty.
Sureness, certainty.
A form of purgatory.
The state of being completely forgotten, of being reduced to a state of non-existence, extinction, or nothingness, including through war and destruction. (Figuratively) for an area like hell, a wasteland.
The state of forgetting completely, of being oblivious, unconscious, unaware, as when sleeping, drunk, or dead.
To consign to oblivion; to efface utterly.