memory hole

Meanings

1. A figurative place to which information is deliberately sent to be forgotten, or to which forgotten or lost information ends up; nowhere, oblivion.
2. A fragment of physical address space which does not map to main memory.
3. Synonym of memory leak (“any of several faults in the memory allocation logic of a computer or program whereby parts of memory become hidden or unusable”).

Etymology

From memory + hole. Sense 1 (“figurative place to which information is deliberately sent to be forgotten, or to which forgotten or lost information ends up”) is a transferred use of the physical slots which the English writer George Orwell (1903–1950) refers to in his novel Nineteen Eighty-Four (1949), into which censored documents for destruction are dropped.