Hepatomegaly refers to:

Hepatomegaly specifically denotes the enlargement of the liver. This condition can be indicative of various underlying health issues, such as liver disease, congestive heart failure, or metabolic disorders. The term itself is derived from "hepato," which is a prefix referring to the liver, and "megaly," which denotes enlargement.

The other options describe different medical conditions unrelated to the liver. Inflammation of the stomach lining pertains to gastritis, weakness in the heart muscle refers to cardiomyopathy, and narrowing of blood vessels is known as stenosis. Therefore, understanding the terminology and roots of medical terms is essential for correctly identifying conditions in the healthcare field, making "enlargement of the liver" the accurate definition of hepatomegaly.