To belch means to let gas escape loudly from your stomach through your mouth, making that distinctive rumbling sound. It happens when air gets trapped in your stomach and needs a way out. You might belch after drinking soda too fast, because the bubbles (carbon dioxide) collect in your stomach and push their way back up through your esophagus.

Some people can belch on command by swallowing air first, though this is usually considered rude in polite company. In many cultures, including most Western ones, belching at the dinner table is seen as impolite, and people say “excuse me” if they accidentally belch in front of others. However, in some cultures, a belch after a meal signals satisfaction and appreciation for good food.

The word can also describe other things that release something forcefully, like when a factory belches smoke into the air or when a volcano belches ash and steam. As a noun, you might hear someone say they let out a loud belch after finishing their root beer float.