What is "air passage"

Usage examples of "air passage".

It had been a relatively simple matter to worm their way down an air passage to its connection with the steps to the covert exit.

There were two tiny holes for the pupils of the eyes, and an air passage replacing the nostrils and septum of the large, hooked nose.

When the three Spindrifters returned home, Chahda had taken air passage to Bombay to see his family.

It had been hollowed out of the cavern wall, perhaps as an air passage to the chambers of the old city, and sloped steeply down.

Krysty kneeled by him, reaching into his open mouth and pulling out sand and strands of weed, making sure his tongue was free of the air passage.