Which term describes an elevated round lesion typically filled with clear fluid?

The term that describes an elevated round lesion typically filled with clear fluid is a vesicle. Vesicles are small, fluid-filled sacs that can develop on the skin or mucous membranes. They are usually less than 1 centimeter in diameter and are common in various skin conditions, such as chickenpox, herpes, and contact dermatitis. The clear fluid within them can be serous, which means it is similar to serum, the clear component of blood.

In contrast, the other terms do not accurately describe this specific type of lesion. A fissure refers to a linear crack or break in the skin, often seen in conditions like athlete's foot. A nodule is a solid, raised lesion that is typically larger than a papule and can involve deeper layers of the skin. A macule is a flat, distinct, discolored area of skin that does not involve any change in texture or elevation. Each of these terms designates different characteristics and types of skin lesions, confirming that a vesicle is indeed the appropriate descriptor for an elevated round lesion filled with clear fluid.