Bloating is a feeling of fullness or tightness in the abdomen that is often accompanied by abdominal pain. It can be caused by gas, indigestion, diet, or even hormones. It can manifest as distention of the abdomen, abdominal pain, and discomfort. It can develop gradually over time or come on suddenly. Bloating can range in severity from mild to severe and can be a symptom of many different underlying medical conditions.