Flatulence is the passage of air or gas from the intestines through the rectum.
The air or gas is called flatus. It is normal to have some flatulence. The average person passes gas through the rectum 8 to 20 times a day. Flatulence is usually a problem only when the gas smells foul, happens frequently, or occurs at inconvenient times. Part of the flatus in the intestine is air that you have swallowed.