A'viary, a building or enclosure for keeping, breeding and rearing birds. The custom of establishing aviaries has been prevalent in all countries since the times of the early Greeks and Romans, and in England we know that they were in use as early as 1577. At the present date, in all of the zoological gardens of Europe and America there are fine aviaries. New York, Washington, Boston, Chicago and other American cities have buildings of this sort, and fine collections of birds are maintained at public expense.