Sudden, forceful, involuntary expulsion of air from the nose and mouth caused by irritation to the mucous membranes of the upper respiratory tract.
A sudden expulsion of air through the nose, designed to expel irritating materials from the upper air passages. In sneezing, a powerful expiratory effort is made, the vocal cords being kept shut until the pressure in the chest has risen high. Air is then suddenly allowed to escape upwards, being directed into the back of the nose by the soft palate. One sneeze projects 10,000 to 100,000 droplets a distance of up to 10 metres at a rate of over 60 kilometres an hour. As such droplets may contain micro-organisms, it is clear what an important part sneezing plays in transmitting infections such as the common cold. Although usually transitory, sneezing may persist for days on end — up to 204 days have been recorded.
Sneezing is an uncontrolled release of air from both the nose and mouth, usually caused by irritation in the upper respiratory tract. This reaction can be triggered by various factors such as the common cold, allergic rhinitis, the presence of excess mucus, or inhaling irritating substances.