stain
noun
a discoloration produced by foreign matter having penetrated into or chemically reacted with a material; a spot not easily removed.
Used to describe an ongoing action or state that is currently taking place in the immediate present.
Examples are provided to illustrate real-world usage of words in context. Any opinions expressed do not reflect the views of Dictionary.com.
Plumes of wildfire smoke are staining skies across the West.
From New York Times ● Jul. 28, 2022