Definition of melanosis in English:



mass nounMedicine
  • A condition of excessive production of melanin in the skin or other tissue.

    • ‘Beyond this observation in 4 patients, we know of no other reports in the English literature of melanosis pigment in the pericolonic lymph nodes of patients with melanosis coli.’
    • ‘Adrenal insufficiency was suspected when five of the following features were present: weight loss, general weakness, anorexia, diarrhoea, melanosis, postural hypotension, hyponatraemia and hyperkalaemia.’
    • ‘Various types of skin manifestations of arsenic toxicity were observed - from melanosis, keratosis, hyperkeratosis, dorsal keratosis, and nonpitting edema, to gangrene and cancer.’
    • ‘A punch biopsy at the border of the lesion is necessary to rule out melanosis secondary to malignant melanoma that manifests as a generalized blue-gray skin discoloration.’
    • ‘Erythema toxicum neonatorum, transient neonatal pustular melanosis, sucking blister, miliaria, and mongolian spots are among the many benign skin conditions that can occur in newborns.’


Early 19th century: modern Latin, from Greek melas, melan- ‘black’ + -osis.