What is the term for a covering placed over a wound or injured part?

The term for a covering placed over a wound or injured part is "dressing." This is a specialized material that protects a wound from infection, absorbs exudate (fluid), and helps facilitate the healing process. Dressings can come in various forms, such as adhesive, non-adhesive, or hydrating, depending on the needs of the wound and the stage of healing.

While related terms such as "bandage," "cast," and "gauze" also pertain to wound care and injury management, they serve different purposes. A bandage is used to secure a dressing in place and may also provide support to a sprain or strain. A cast is a rigid support used to immobilize broken bones during healing, while gauze is a type of fabric often used as a part of a dressing but does not, on its own, provide the complete coverage or protective qualities that a dressing does.

Thus, "dressing" accurately identifies the specific type of covering meant to be placed over a wound to ensure proper care and healing.