Naeveus is a medical term used to describe a type of skin lesion. It is commonly referred to as a MOLE or BIRTHMARK. The term naeveus is derived from the Latin word for 'BIRTHMARK' and is used to describe a variety of benign skin lesions, including moles, freckles, and other discolorations. These lesions can be either flat or raised and can vary in color from light brown to black. They are usually harmless and do not require treatment, but they can be removed if desired.