Picture of Dysplastic Nevus
Dysplastic nevus: An atypical mole whose appearance is different from that of a common ordinary mole. Dysplastic nevi tend to be larger than ordinary moles, have more irregular borders, are often mixed in color and present in large numbers. A dysplastic nevus can give rise to malignant melanoma.
Source: MedTerms™ Medical Dictionary by MedicineNet, Inc.