A hiccup is a sudden spasm of the muscle that separates the chest from the belly area. This muscle is called the diaphragm. The spasm occurs unintentionally. Each spasm is followed by a quick closing of your vocal cords, which leads to the characteristic "hiccup" sound. This pair of events usually repeats a few times in a row. Hiccups are usually just a nuisance and disappear on their own after a few minutes. Rarely, a person may have long-term (chronic) hiccups, which last for days to months. Follow the links below to find WebMD's comprehensive coverage about how hiccups develop, the causes, how to treat them, and much more.