What is the term for a flat, discolored area on the skin that is less than one centimeter in diameter?

The term that describes a flat, discolored area on the skin measuring less than one centimeter in diameter is a macule. Macules are typically not raised and can vary in color, but they must meet the criteria of being flat and less than a centimeter. They can appear as freckles, small age spots, or other forms of skin discoloration.

In contrast, a patch refers to a larger area of discoloration that typically exceeds one centimeter. A vesicle is a small fluid-filled blister, and a bulla is a larger fluid-filled blister. Both vesicles and bullae are elevated lesions and not flat like macules. This distinction is crucial for accurately identifying various skin conditions and their characteristics.