Final answer:
The suffix '-atresia' in medical terminology signifies the closure or absence of a normal body opening or passage, and is commonly used to describe conditions where a structure is abnormally closed or blocked.
Step-by-step explanation:
The suffix '-atresia' in medical terminology refers to the closure or absence of a normal body opening or passage. It is commonly used to describe conditions where a structure, such as a blood vessel or a tube, is abnormally closed or blocked. For example, esophageal atresia refers to the abnormal closure of the esophagus, and biliary atresia refers to the blockage or absence of the bile ducts.