This is the 14180th most frequent German word.
grau
Gray (a color).
In this sentence, "grau" is used as an adjective to describe the color of the sky, indicating it is cloudy.
Der Himmel ist heute grau.
The sky is gray today.
Here, "grauen" is the inflected form of the adjective "grau," agreeing in case and gender with the noun "Mantel" (coat).
Sie trägt einen grauen Mantel.
She is wearing a gray coat.
"Grau" is employed metaphorically to describe a mood or atmosphere, suggesting dullness or monotony.