Dictionary
bird•cage
Pronunciation: (bûrd'kāj"), [key]—
n.
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.
Random House Unabridged Dictionary, Copyright © 1997, by Random House, Inc., on Infoplease.