epidermal cyst
a benign cyst derived from the epidermis or the epithelium of a hair follicle, formed by cystic enclosures of epithelium within the dermis, becoming filled with keratin and lipid-rich debris. Types include dermoid cyst, epidermal inclusion cyst, pilar cyst, milium, and steatocystoma. Called also epidermoid or epithelial c.
Medical dictionary.
2011.