dermat(o)-

Sometimes derm(o)-.

The skin.

Greek derma, dermat‑, skin or hide.

Dermatology is the branch of medicine concerned with the diagnosis and treatment of skin disorders, such as dermatitis, a condition of the skin in which it becomes red, swollen, and sore; dermabrasion is the removal of superficial layers of skin with a rapidly revolving abrasive tool, as a technique in cosmetic surgery; dermatoglyphics is the study of skin markings or patterns on fingers, hands, and feet, and its application, especially in criminology.

The form dermo‑ was once common but now largely replaced by dermato‑; surviving examples include dermoid, relating to the skin, usually found in dermoid cyst, an abnormal growth containing skin cells, hair follicles, and sebaceous glands; and dermographism (Greek ‑graphia, writing), a local reaction caused by pressure on the skin, such that it can be ‘written’ on, producing welts.