noun
: the air-bearing portion of the respiratory system in which no significant gaseous exchange takes place and which includes the air-conveying ducts from the nostrils to the terminal bronchioles
noun
: the air-bearing portion of the respiratory system in which no significant gaseous exchange takes place and which includes the air-conveying ducts from the nostrils to the terminal bronchioles
Webster's New International English Dictionary. Новый международный словарь английского языка Webster. 2012