Blacken (verb)

1. To make something dark or black in color.
2. To discolor or tarnish something.

Origin:

The word blacken comes from the adjective black meaning dark or having the color black. it refers to the process of making something dark or black in color.

Examples:

1. The fire blackened the walls of the building.
2. He blackened the steak before grilling it.
3. The metal was blackened by the heat.
4. The skillet needs to be blackened before it can be seasoned.
5. The soot blackened her face.