What does the term "subcutaneous" refer to?

The term "subcutaneous" specifically refers to the layer of tissue that lies beneath the skin. It is derived from the Latin roots "sub," meaning beneath, and "cutis," meaning skin. Subcutaneous tissue is primarily composed of fat and connective tissue, and it serves as insulation, energy storage, and a cushion for the body. In a medical context, when referring to subcutaneous injections, it indicates that the medication is administered into this layer to ensure proper absorption into the bloodstream. This precise definition clarifies that the term is not associated with the skin surface, the bloodstream, or locations above the skin.