• (mole) A benign (not cancer) growth on the skin that is formed by a cluster of melanocytes (cells that make a substance called melanin, which gives color to skin and eyes). A mole is usually dark and may be raised from the skin.
  NCI Dictionary of Cancer Terms
  U.S. National Cancer Institute, 2021
• (nevus, pigmented) A nevus containing melanin. The term is usually restricted to nevocytic nevi (round or oval collections of melanin-containing nevus cells occurring at the dermoepidermal junction of the skin or in the dermis proper) or moles, but may be applied to other pigmented nevi.
  NLM Medical Subject Headings
  U.S. National Library of Medicine, 2025
• A neoplasm composed of melanocytes that usually appears as a dark spot on the skin.
  NCI
  U.S. National Cancer Institute, 2021
• A oval and round, colored (usually medium-to dark brown, reddish brown, or flesh colored) lesion. Typically, a melanocytic nevus is less than 6 mm in diameter, but may be much smaller or larger.
  Human Phenotype Ontology (HPO)
  The Human Phenotype Ontology Project, 2025
• Melanocytic nevi are benign neoplasms or hamartomas composed of melanocytes, the pigment-producing cells that constitutively colonize the epidermis. Melanocytes are derived from the neural crest and migrate during embryogenesis to selected ectodermal sites (primarily the skin and the CNS), but also to the eyes and the ears.
  Medscape
  WebMD, 2025