“Eigengrau” is a German loanword used to describe the specific color of total darkness as perceived by human eyes. Rather than black, the color that human optic nerves discern in pure darkness is a dark gray, which is why eigengrau is sometimes called “brain gray.” Eigengrau is close to what might be called “charcoal gray,” but the word’s German roots specify that this is a gray created inside the viewer’s brain. In German, “eigengrau” translates to “own gray,” or “intrinsic gray,” suggesting the shade might shift, depending on the viewer’s perception.