Airway is a noun meaning "a passage for air, especially the breathing passages of the body". Historically, it is a compound of air + way ('path, route'), from Old English weg; first used of ventilation passages and later of breathing passages and flight routes. The visible construction is part of the etymology: airway is not just an unanalyzed simple word. The semantic history matters here: the earlier use is the starting point, and the modern sense, "a passage for air, especially the breathing passages of the body", is the later or specialized English value. The historical chain links Latin āēr with Old English weg. Close English family members include air, way, and airways.