Final answer:
GERD stands for Gastroesophageal Reflux Disease and refers to a condition where the lower esophageal sphincter fails to close properly, allowing stomach contents to enter the esophagus. This can cause heartburn and potentially damage the esophageal lining.
Step-by-step explanation:
The term GERD stands for gastroesophageal reflux disease. GERD occurs when the lower esophageal sphincter, which normally remains closed to prevent stomach contents from entering the esophagus, fails to function properly. This can lead to heartburn and, if it becomes chronic, may cause damage to the esophageal lining.