Birthmark

Birthmark, skin blemish, usually congenital. There are 2 main types: pigmented nevuses or moles, which are usually brown or black and may be raised or flat; and vascular nevuses or hemangiomas, local growths of small blood vessels, such as the “strawberry mark” and the “portwine stain.” Although harmless, they are sometimes removed for cosmetic reasons or if they show malignant tendencies.

See also: Mole.