Slough (Noun)

The doctor carefully debrided the wound, removing the slough of dead tissue that was preventing it from healing properly.
As the gangrene advanced, the patient's skin began to turn black and form a large slough that was painful to the touch.
After several days of infection, a foul-smelling slough developed on the surface of the boil, requiring surgical intervention.
The nurse gently cleaned the wound, paying special attention to the area of slough that was surrounding the dressing.
The patient's condition worsened when a large slough of necrotic tissue separated from the surrounding skin, forming a deep cavity.

Any outer covering that can be shed or cast off (such as the cast-off skin of a snake).