/wʌn lʌŋ əˈpɑːrtmənt/ noun phrase
Definition: A “starter” apartment that is so small you can barely fit your second lung into it.
Etymology
A biological metaphor for extreme spatial constraints. While a “studio” or “efficiency” might sound professional, “one lung” accurately describes the physiological sensation of living in a space where you can barely draw a full breath without hitting a wall. It is the architectural equivalent of “house arrest” for your furniture. The term implies that the unit is a temporary logistical necessity rather than a long-term residence—a place where one “starts” before moving on to an apartment that allows for bilateral respiration.
Usage
Context: Used with “low-friction” candor to describe the reality of high-density urban living. It is a way to “own up” to a cramped living situation without the flattery of real estate jargon like “cozy” or “intimate.” It suggests that the inhabitant is currently in a “dry dock” phase of their career or life.
In a sentence: “It’s a great location in the city, but it’s definitely a one lung apartment; I have to step into the hallway just to change my mind.”