The medical term for tissue cell death in the skin is necrosis. Necrosis is a form of cell death that occurs due to a lack of oxygen and nutrients to the affected tissue. It can be caused by a variety of factors, including trauma, infection, and certain medical conditions. Necrosis can range in severity from superficial, affecting only the outer layers of the skin, to deep, involving the entire thickness of the skin. Treatment for necrosis typically involves removing the dead tissue and promoting wound healing.