The phrase denotes a general concept related to avian creatures observed in aerial environments. For example, a child might use this terminology to describe any type of flying animal they see outdoors, particularly if they are unfamiliar with specific species.
This type of generalized description serves a fundamental purpose in early learning and communication. It allows individuals to categorize and discuss observations even without possessing a detailed vocabulary. Historically, such broad categorizations represent a primary step in the development of more sophisticated understanding of the natural world.