I have heard the phrase 'down the memory hole' used before, and I believe it to have originated in the novel 1984 by George Orwell, but I'm not 100% sure the definition I've found is right:
memory hole
noun
a piece of one's memory that seems to be missing; also, a place where lost memories seem to goWord Origin
modeled upon black holememory hole. Dictionary.com. Dictionary.com's 21st Century Lexicon. Dictionary.com, LLC. http://www.dictionary.com/browse/memory-hole (accessed: April 21, 2016).
My understanding was that the phrase refers to something deleted or removed because something about it was likely to cause embarrassment or lost reputation to a person, or to persons, related to it.
Like if there was a book, or a photograph, or even a post on here, which was completely erased, because some people didn't want to be associated with it in some way…
My feeling is this rendering could use some tuning, though, so I was wondering if anyone could provide a more authoritative definition.
Best Answer
The protagonist of 1984, Winston, works in the Ministry of Truth, which is responsible for editing all documentation that conflics with the current positions and declarations of the state. Winston's workplace is described as follows:
All conflicting evidence goes down the memory hole, as does any paper evidence of Winston's work to rewrite the past. So the memory hole is the place that all evidence of contradiction goes to be destroyed. In 1984, it's evidence that the state finds inconvenient. As a metaphor, it's anything that a person finds distasteful enough to wish eradicated.