What is hiccup?

Hiccup or Hiccough, is a spasmodic movement of the diaphragm, brought suddenly to a stop by the closing of the cleft between the vocal cords. It is caused by some abnormal irritation of the phrenic, that is, the diaphragmatic nerve. The ordinary case of hiccup is little more than a momentary inconvenience, resulting from indigestion. Occasionally it assumes a more serious character and becomes difficult to stop. In such instances it is the symptom of some diseased condition indicating the need of a physician. Ordinary cases of hiccup may be relieved by drinking cold water, or by holding the breath for a few seconds.