A pied-à-terre is a small living unit, e.g., apartment or condominium, often located in a large city and not used as an individual's primary residence. The term implies use of the property as a temporary second residence, but not a vacation home, either for part of the year or part of the work week, usually by a reasonably wealthy person. If the owner's primary residence is nearby, the term also implies that the residence allows the owner to use their primary residence as a vacation home.

Billionaires' Row is the name of a group of ultra-luxury residential skyscrapers, and the area surrounding them, near the southern end of Central Park in Manhattan, New York City. Several of these buildings are in the supertall category, taller than 1,000 feet (300 m), and are among the tallest buildings in the world. Since most of these pencil towers are on 57th Street, the term can refer to this street, too.