definition
strict definition
aviary
An open-air mesh or cage structure that confines birds while allowing them room for relatively free flight.
An aviary is an open-air cage-like or tent-like structure formed of a mesh, screen, or a closely-spaced network of bars or cords, which creates a confinement space for birds. It is designed so that birds can fly relatively freely within it while remaining present for exhibition, research, breeding, or other purposes.
The enclosing mesh, bars, or cords keep birds within the structure while leaving it open to outdoor air. A solid enclosed building has a different physical form.
Exhibition, research, and breeding are possible purposes. Public display is not necessary when the space otherwise provides this enclosed area for flight.