Grey

Grey was a color.

Earth in the 30th century had grey land and gey seas, with grey cities linked by grey highways across grey deserts. (TV: The Mutants)

The Inter Minorians had grey skin, (TV: Carnival of Monsters) as did the Grey Man's race. (PROSE: Falls the Shadow)

The Renegade Daleks had grey and black casings. (TV: Revelation of the Daleks, Remembrance of the Daleks)