Heartburn is a common condition. It often follows a binge at the buffet or a stressful day at work. Heartburn can make you uncomfortable and even disturb your sleep. But if you get heartburn more than twice a week, you may have a condition known as GERD. GERD stands for gastroesophageal reflux disease. Gastroesophageal refers to your stomach and esophagus. The esophagus is the tube that carries food from your mouth down to your stomach. Reflux means to flow back. Gastroesophageal reflux is the return of stomach acid and food from your stomach, back up your esophagus.