brown spot; brown patch; chloasma
Medical term for a brownish discoloration on the skin, including freckle-like spots, age spots, or melasma/chloasma. Used in dermatology contexts.
I developed brown spots on my face and had them checked at a dermatology clinic.
Compound of 褐色 (brown color) + 斑 (spot, patch). A straightforward Sino-Japanese medical term.