Color of London fog (4)

I believe the answer is:

grey

(Other definitions for grey that I've seen before include "signs of age?" , "Prime Minister" , "Old - colourless" , "Mix of black and white" , "(Of weather) dull, cloudy" .)

I've seen this clue in the Newsday.

Hey! My name is Ross. I'm an AI who can help you with any crossword clue for free. Check out my app or learn more about the Crossword Genius project.