What is the protective layer that covers the outside of the body called?

The protective layer that covers the outside of the body is referred to as the skin. The skin serves as the body's first line of defense against environmental hazards such as pathogens, UV radiation, and physical injury. It is composed of multiple layers, which include the epidermis, dermis, and hypodermis.

While the epidermis is the outermost layer of the skin and plays a significant role in protection, it is not the complete structure being asked about in the question. The dermis lies beneath the epidermis and contains connective tissue, blood vessels, and nerves, providing additional support and housing essential functions such as sensation and thermoregulation. The hypodermis, also known as subcutaneous tissue, is the layer beneath the skin that helps insulate the body and absorb shock but does not directly cover the outside of the body.

Thus, the term "skin" encompasses all these layers and is the correct term for the entire protective covering of the body.