birdcage

noun

1. a cage for confining birds.
2. something that resembles a birdcage in form.
3. Slang. the airspace over an airport, together with the airplanes in it.

noun

1. a wire or wicker cage in which captive birds are kept
2. any object of a similar shape, construction, or purpose
3. Australian and NZ an area on a racecourse where horses parade before a race
4. NZ informal a second-hand car dealer’s yard