/ðə bɪɡ haʊs/ noun phrase / euphemism
Definition: Off to prison. No need to admit a member of the family has misbehaved when you can simply state that s/he is now living in The Big House.
Etymology
Originally 19th-century underworld slang for a large state prison, the term was adopted by upper-class social circles as a “low-friction” way to handle scandal. Rather than detailing a “P.D.M.” in a courtroom, a family can suggest the relative has simply moved to a substantial, albeit involuntary, residence. It frames the incarceration as a change in “logistics” rather than a moral failure. It is the ultimate “dry dock”—a place where one’s “runway” is restricted by the state.
Usage
Context: Used to provide “honest feedback” about a family member’s whereabouts while maintaining a “graceful exit” from further questioning. It implies the individual is currently under “house arrest” on a much larger, institutional scale. It is the “plain language” equivalent of saying someone is “detained at the government’s expense.”
In a sentence: “We won’t be seeing much of my cousin for the next five to ten years; he’s moved into the big house upstate.”