Soot (noun)

A black powdery or flaky substance consisting largely of amorphous carbon, produced by the incomplete burning of coal, oil, wood, or other organic matter.

Origin:

The word soot comes from old english sōt which means "soot" and it is derived from proto-germanic word "sutaz".

Examples:

1. The chimneys were black with soot.
2. He cleaned the soot off the fireplace.
3. The walls were covered in soot from the fire.
4. Soot is a major contributor to air pollution.
5. The artist used soot to create the dark backgrounds in his drawings.