The process of adding water to a gas making it humid or moist, humidifier.
The air we breathe must be moist for the efficient working of the lungs. Humidification, or moistening of the air, is achieved largely by the nose, which acts as an air-conditioner, warming, moistening, and filtering the 10,000 litres of air which we inhale daily; in this process it produces around 1-5 litres of secretion daily.