bronchiole /brong″kē·ōl/ [L, bronchiolus, little windpipe] , a small airway of the respiratory system extending from the bronchi into the lobes of the lung. There are two divisions of bronchioles: The terminal bronchioles passively conduct inspired air from the bronchi to the respiratory bronchioles and expired air from the respiratory bronchioles to the bronchi. The respiratory bronchioles function similarly, allowing the exchange of air and waste gases between the alveolar ducts and the terminal bronchioles. −bronchiolar, adj.
