interdigitation

This term is primarily used in technical, biological, and anatomical contexts to describe a specific type of interlocking mechanism. It evokes the image of fingers interlacing, where the protrusions of one surface fit precisely into the recesses of another to create a strong, stable bond or to maximize contact area.

In medical and histological descriptions, it is often used to explain how different tissue layers, such as the dermis and epidermis, adhere to one another. Because it describes a structural state or a biological process, it is typically treated as an uncountable noun in scientific literature, though it can be used countably when referring to specific instances of such interlocking.