For the aerial route, see Airway (aviation). The word airway is also used sometimes to mean an airliner flight route, and thus the word "Airways" often occurs in names of companies who run airliners.

The airways are those parts of the respiratory system through which air flows between the external environment and the alveoli.

Protection of the airways

1. The epithelial surfaces of the airways contain cilia. Inhaled particles stick to mucus (secreted by goblet cells) which is continuously removed from the airways by these cilia. The airway epithelium also secretes a watery fluid upon which the mucus can ride freely. The production of this fluid is impaired by the disease cystic fibrosis.
2. Macrophages are present in the airways. These cells protect the airways from infection by engulfing inhaled particles and bacteria.