Which term would describe a narrowing of a canal or duct?

The term that describes a narrowing of a canal or duct is atresia. Atresia specifically refers to the absence or closure of a normal body opening or passage, which often manifests as a narrowing in various anatomical structures, such as the intestines or other ductal systems. This condition can lead to significant physiological issues because normal flow or communication through those ducts or canals is obstructed, impacting various bodily functions. Understanding atresia is important in medical contexts, particularly in congenital conditions where such narrowing can affect patient outcomes and require surgical intervention. The other terms listed, while relevant to medical terminology, refer to different conditions or anatomy.