How can a skin lesion characterized by raised, itchy areas of localized swelling be defined?

A skin lesion characterized by raised, itchy areas of localized swelling is defined as a wheal. Wheals are often the result of an allergic reaction or other stimuli causing localized swelling in the skin. They typically appear suddenly and can vary in size and shape, often with a paler center and a red halo surrounding them. This understanding of wheals is essential in recognizing various skin conditions and their potential underlying causes.

In contrast, blisters are fluid-filled sacs that form on the skin due to friction, burns, or other forms of irritation; macules are flat, discolored spots on the skin that do not protrude above the surface; and pustules are small bumps on the skin that contain pus. Each of these conditions has distinct characteristics that differentiate them from wheals, reinforcing why wheal is the correct term for raised, itchy lesions resulting from localized swelling.