Definition of "acanthosis" []

• A name applied to any disease affecting primarily the stratum spinosum (prickle-cells) of the epidermis. (noun)

The Century Dictionary (Public Domain)

• "Look at the skin on your neck, to see if it has a dark, velvety appearance a condition called acanthosis nigricans."
• "He had a dark skin coloring on the back of his neck called "acanthosis nigricans," which can be a sign of being prediabetic."
• "This condition—called acanthosis nigricans—is an early sign of metabolic syndrome, which is associated with high blood pressure plus elevated levels of blood lipids and blood sugar."