Gray

1. Of or relating to an achromatic color of any lightness between the extremes of black and white. Sometimes spelled as grey. Some like the color gray; other think it too somber.
2. Dull or dark. It was a rather gray, rainy afternoon.
3. Lacking in cheer. She was in a gray mood after the illness of her mother.
4. Intermediate in character or position, as regard to a subjective matter. There is a gray area between their differing opinions on the film's morality.